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THE WEST AFRICAN EXAMINATIONS COUNCIL

[

LIBERIA SENIOR HIGH

SCHOOL CERTIFICATE

EXAMINATION (LSHSCE)

DECEMBER 2010 CHIEF EXAMINERS’ REPORTS

LIBERIA

SUBJECT/PAPER PAGE

GENERAL RESUMÉ i – ii ENGLISH LANGUAGE English Language 1 – 5 GENERAL SUBJECTS Economics 6 – 14 Geography 15 – 26 History 27 – 32 Literature-in-English 33 – 41

MATHEMATICS Mathematics 42 – 49

SCIENCE SUBJECTS Biology 50 – 58 Chemistry 59 – 68 Physics 69 - 77

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THE WEST AFRICAN EXAMINATIONS COUNCIL

MONROVIA, LIBERIA

GENERAL RESUMRÉOF THE CHIEF EXAMINERS’ REPORTS FOR THE DECEMBER 2010 LIBERIA SENIOR HIGH SCHOOL CERTIFICATE EXAMINATION

1. STANDARD OF THE PAPERS

The Chief Examiners observed that the papers were within the scope of the prescribed

Examination Syllabus and they compared favorably with those of previous years. They

further agreed that the rubrics were simple, straightforward and unambiguous.

2. CANDIDATES’ PERFORMANCE

With the exception of Economics(P. 6) in which candidates’ performance was rated fair,

Chief Examiners of the various papers observed that the general performance was rather

unsatisfactory: English Language(P.1), Geography(P.15), History(P.27), Literature-in-

English(P.33), Mathematics(P.42), Biology(P.50), Chemistry (P.60) and Physics (P.70).

3. CANDIDATES’ STRENGTHS

The Chief Examiners commended candidates for exhibiting remarkable strengths in the

following areas:

(a) Understanding of Rubrics

Unlike past candidates, a good number of the candidates understood the rubrics

and followed them. ie- Economics (P.6), Literature-in- English (P.33), History (P.27)

(b) Understanding of Aspects of the Content and Logical Presentation of Relevant

Material. Eg: Electronic Configuration and concept of organic Chemistry(P.60),

Human Biology, Biology(P.50), Physical Terms-Physics(P.70), Essay Topics-

English Language(P.1), Important Terminologies Literature-in- English(P.33), Well

drawn Diagrams/Maps-Geography (P.15), Improved Penmanship- Literature-in-

English (P. 33).

4. CANDIDATES’ WEAKNESSES

The Chief Examiners observed the following as weaknesses exhibited by candidates:

(a) Chief Examiners reported candidates’ inability to read and understand questions and

provide appropriate answers. Poor spelling, grammar and expression prevented most

candidates from attaining good marks- English Language (P.1), Geography (P.15),

History (P.27), Literature-in-English (P.33), Biology (P.50).

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(b) Disregard of Rubrics-Some candidates answered several questions on a page or more

than the required number of questions from a given section-Economics (P.15),

Mathematics (P.42), Physics (P.70).

(c) Almost all Chief Examiners complained about candidates’ lack of content and

unfamiliarity with prescribed texts, topics, etc; hence, inadequate/sketchy answers,

poorly drawn and labeled diagrams; inability to explain/translate scientific terms,

concepts/theories e.g. Geography (P.15) History (P.27), Literature-in-English (P.33),

Biology (P.50), Chemistry (P.60), Physics(P.70).

5. SUGGESTED REMEDIES

The Chief Examiners for the various papers have unanimously advanced the following as

ways by which future candidates could improve their performance:

Candidates should be

(1) encouraged to attend tutorial classes or form study groups to prepare themselves

effectively for the Examination;

(2) drilled on literary, scientific and mathematical terms etc.;

(3) instructed on how to allocate time to important and less important Questions;

(4) exposed to relevant reading materials, past WAEC question papers, Chief Examiners’

Reports, etc.

(5) drilled to improve their penmanship, spelling, grammar, lexis, etc.;

(6) assisted to develop reading, comprehension and composition skills;

(7) taught to analyze questions and answer them fully; and

(8) instructed on the importance of the rubrics.

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ENGLISH LANGUAGE 2

1. GENERAL COMMENTS

The standard of the paper compared favorably with those of previous years. The questions

were fair, straight – forward and unambiguous. However, the general performance of

candidates was not encouraging.


The range of questions and their requirements reflected candidates’ day-to-day language use.

They therefore understood the questions well and responded accordingly. No candidates

wrote an essay for a question requiring a letter. However, a good number of them responded

with sufficient details on essay questions that in previous exams went unanswered.

3. CANDIDATES’ WEAKNESSES The following weaknesses were observed in most of the candidates’ papers:

(1) Misplacement and omission of formal features of letters

(2) Inappropriateness of diction used in conventional salutation and closing.

(3) Illegibility of handwriting

(4) Lack of knowledge of the organizational structure (Introduction, Body, and

Conclusion) of an essay and the specific functions of each element in the essay

structure.

(5) Non-completion of letters and the essays (probably owing to the expiration of

stipulated time)

(6) Poor reading comprehension and vocabulary skills as evidenced by the imbalanced

correlation between comprehension questions and Candidates’ responses.

4. SUGGESTED REMEDIES/RECOMMENDATIONS

Schools, particularly English Language instructors, should stress candidates’ skills in the

areas of reading comprehension and essay composition.

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5. DETAILED COMMENTS ON INDIVIDUAL QUESTIONS

QUESTION #1

A recently established vocational/Technical institution has put an advertisement in a

local newspaper asking high school graduates to apply for admission to pursue degree

programs in the various trades. Write a letter of application for enrollment to the Dean

of Admission and Records and state your area of interest.

Candidates should have provided the formal features of a formal letter. In the introduction

candidates should have stated what they were applying for and to provide the source of

information/advertisement. They should have provided information about themselves and

the schools attended, with dates; and subjects studied and certificates obtained. They should

have given reasons why they really wanted to be admitted. It was optional to provide names

and addresses of two references.

QUESTION #2

Your newly installed D.S.T.V. set is not functioning properly. Write a letter of

complaint to the Sales Manager of OPONCO ELECTRONICS, Camp Johnson Road,

Monrovia, Liberia, describing the problems and asking for servicing or replacement.

This was a formal letter. Candidates should have written out all the required formal features;

provided the date the item was bought and the Receipt Number (if possible). Candidates

should have described the problem and requested the Sales Manager to either repair or

replace the set.

QUESTION #3

Your school is being challenged by a sister school on proposition “Girl-child’s

Education is more Important Than Boy-Child’s”. As a member of your School

Debating Club, write your statement for or against the proposition.

In recent years, girl’s education has come to the apex of national concern, and it is

appropriate that a national examination like WAEC presents the issue in a way that

accommodates diverse opinions. It is explicit that the question, as a debatable topic, demands

an argumentative development that restricts candidates’ argumentation to one or two sides of

the proposition, thus eliminating any middle-of-the-road development.

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Majority of the candidates wrote elaborately on affirmation of the proposition that girls’

education is more important than boys’. Interestingly, some male candidates themselves

swallowed their pride or biases and affirmed the proposition staunchly.

However, a few number of male candidates rejected the pros of the proposition maintaining

that female education ends up in the home and is retarded by the majority role of child

bearing.

All of the candidates who attempted the question had interesting points. However, most of

them did not observe the organizational structures of a debate paper. There were not the

usual vocative-addresses to the judges, fellow debaters or audience. This essential element

of a debate presentation was left out.

QUESTION #4

In contemporary Africa, Military Intervention in Politics should be resisted.

Discuss.

This was the least attempted question. Few of the candidates attempted the question. Worse

still, this small percentage of candidates discussed war in general instead of discussing

politics and the military intervention in it. Of course, the question required candidates to take

sides; it was not a question for a mere discussion.

QUESTION #5

As a member of the House of Representatives of the National Legislature, which do you

prefer as a development project to your constituency, electricity or safe drinking

water? Select your preference and discuss it.

Surely this question was somehow misunderstood by most candidates who attempted it.

First, they wrote to a member of the House of Representatives asking for support for a

project. Little did the candidates know that they themselves were to assume the position of a

Representative deciding on the most urgent or suitable project(s) to carry out in their

constituencies. Secondly, some candidates thought they were required only to develop a

project proposal and submit it to their constituencies.

However, most candidates avoided this question and only very few of them who did attempt

the question expressed preference for training in important vocations like Mechanical and

Civil Engineering.

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QUESTION #6

As the President of the Community Development Foundation, you received a grant of

five hundred United States dollars for projects. Write a report to the donor, detailing

how the money was spent and make recommendations for additional.

Here, candidates demonstrated extreme ignorance of the conventions of report writing.

Majority of the candidates who attempted the question wrote the details of their reports

haphazardly; there was no clear degrees of pattern as all the details were jumbled in one

paragraph. Few of the candidates even wrote a letter instead of a report. Of course, there

were few good reports, but these fell short mostly to organize or itemize the presentation of

income and expenditure.

QUESTION #7

Read the following passage carefully and answer all the questions which follow. Give

brief but precise answers to the questions.

Kolleh Cornormia had just finished reading an exciting African novel which he

borrowed from the A.M.E. Zion University College library. It was about some boys

who discovered a hidden treasure. They were all alone on a rocky part of the beach

when, suddenly, Kollie fell against a big boulder which rolled aside to reveal the

entrance to a cave. “Let’s look in here’’, he cried. Jallah and Sieh eagerly followed him.

Inside was a long, low passage and there was sufficient light for them to see that there

were mysterious markings on the walls. They crept along very cautiously and soon

came to a large cavern. In the middle, there stood three large chests, rusty and green

with age, and nearby another smaller one. Sieh said,” let’s open them and see what’s

inside”.

They struggled with the locks for some time and, in the end, managed to open them

with a penknife. To their astonishment they found that the chests were filled with

precious jewels such as diamonds, emeralds and rubies.

(a) Give a brief and precise description of the entrance to the cave as

mentioned in the passage.

(b) What does the word “reveal”, as used in the passage mean?

(c) What does the writer mean by “passage” in this story?

(d) Comprehensively name the precious jewels as mentioned in the

passage.

(d) What is the main idea of the passage?

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One big problem observed was that most of the candidates’ responses to the

comprehension question were not precise; they wrote out several sentences for some

questions that required a single sentence. The second problem is that they did not

paraphrase or rephrase, and in most cases some tried to do so but they committed

serious grammatical blunders, particularly in the changing of pronoun references and

verb tenses.

In another vein, those candidates who attempted this question could not define

“reveal’ and “passage” or provide an alternative word that suits the use of the word in

the context.

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ECONOMICS 2

1. GENERAL COMMENTS

The standard of the paper compared favorably with those of the previous years.

It was consistent with the demands of the prescribed WAEC Syllabus. Results from scripts

marked indicate an overall fair performance of the candidates.


A few of the candidates performed well in answering some of the questions. Candidates

demonstrated their ability and performed well on questions 5, 7, and 9.They followed the

rubrics.


The weaknesses of the candidates were generally observed to fall in two categories:

(1) Poor composition – Some candidates were unable to write answers that were free

from grammatical errors;

(2) Calculations – A majority of the candidates was unable to calculate price elasticity

and quantity.

4. SUGGESTED REMEDIES Candidates should be encouraged to review past examination papers to enhance their

skills and performance on the date and graphical response questions. Chief Examiners’

Reports should be available to candidates.

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5. DETAILED COMMENTS ON INDIVIDUAL QUESTIONS QUESTION #1

The data below illustrates the demand and supply of a commodity in a certain market.

Use the information from the data below to answer question # 1.

PRICE QUANTITY DEMANDED QUANTITY SUPPLIED

5 10 15 20 25 30 35 40 45

1200 1100 1000 900 800 700 600 500 400

400 500 600 700 800 900

1000 1100 1200

(a ) Graph the demand and supply schedule for the above market.

(b) Assume that the price in the market increases from L$ 5.00

to L$ 10.00 and quantity demanded decrease from 600 to 500 units; calculate the price elasticity of demand?

(c ) Assume that the market demand schedule for a commodity is

Qd = 1200 – 5P and the market supply schedule is Qs = - 900 + 30P; calculate the quantity traded.

This question was attempted by very few candidates. They attempted unsatisfactorily to graph a supply and demand curve. They could not adequately calculate

the price elasticity of demand.

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The candidates were expected to provide the following answers:

1. ( a )

P

45 D . .S

40 . .

35 . .

30 . .

25 .

20 . .

15 . .

10 . .

. D

5 S .

0 400 500 600 700 800 900 1000 1100 1200

Q

(b) Price Elasticity of Demand = Q X P

P Q

P E D = 100 x 5

5 500 Q = 500 – 400 = 100 P = 5.00 10.00 = 5.00

P E D = 1/5 or 0.2

(c) Qd = 1200 – 5P

Qs = - 900 + 30P Q d = Qs = 1200 – 5P - 900 +30P Qd = 1200 – 5( 60 ) 35P = 2100 Qd = 1200 – 300 35 35 Qd = 900

P = 60

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QUESTION #2 Use the graph below to answer question two:

Arms I

20,000 18,000 II

16,000 III L M

14,000 IV Z

12,000 V

0

VI

7000 10000 13000 16000 19000

Rice

(a) What does the line I – IV represent? (b) What does the point Z indicate? (c) What does the point L indicate? (d) What does the point M indicate?

This was one of the least attempted questions. Those who attempted it did not

perform well.

The candidates were required to provide the following answers: (a) the line I – VI represents a Production Possibility Frontier (PPF Curve); (b) the point Z indicates that resources are inefficiently utilized; (c) the point L indicates unattainable; and (d) the point M indicates a situation where resources are fully

utilized.

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QUESTION #3 List and explain four factors responsible for traffic congestion in and around the city of Monrovia.

This was a popular question which was attempted by a majority of the candidates. Their performance was satisfactory.

The candidates were expected to list and explain any four of the following factors: (a) Lack of road network; (b) Increase in the number of cars and road users; (c) Lack of road maintenance; (d) Lack of traffic lights at strategic intersections; (e) Increase in the number of street peddlers/sellers; (f) The problems created by traffic police and inappropriate traffic control mechanism.

QUESTION #4 List and define four branches of economics. This was an unpopular question which was least attempted. A few candidates attempted but did not follow the rubrics of the question. They were expected to provide the following answers on any of the branches of

economics:

(a) Public Finance – a branch of economics which studies the financial activities of government revenue, expenditure and debt management.

(b) Money and Banking – a branch of economics which studies money and interest rate.

(c) International Economics – a branch of economics which studies how and why trade occurs between and among countries.

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(d) Development Economics – a branch of economics which studies issues of how and why development occurs within societies.

(e) Transportation Economics – a branch of economics that studies transportation as a sector of an economy.

(f) Agriculture Economics – a branch of economics which studies the relationship of agriculture and the production of allied products or crops.

QUESTION #5 List and define four types of business organizations. This was a popular question which was attempted by majority of the candidates. They were expected to list and explain the following types of business organizations:

(a) Proprietorship - a form of business organization in which one person has direct ownership of the business.

(b) Partnership – a form of business organization in which two or more persons or people share direct ownership of the business.

(c) Corporation – a form of business organization which is created by an article of incorporation and registered according to law.

(d) Joint stock Company – is an association of people who contribute for the purpose of

carrying out economic activities.

QUESTION #6

Define the following concepts: (a) Merchant; (b) Industry; (c) Investment; (d) Wealth; (e) Graph; (f) Economy.

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This question was attempted by a majority of the candidates. They were capable of

adequately defining few of the concepts.

The candidates were required to provide the following answers:

(a) Merchant – a person who buys and sells commodities.

(b) Industry – a group of firms producing similar goods.

(c) Investment – expenditure made by firms, businesses or individuals to increase capital.

(d) Wealth – production which yields utilities.

(e) Economy – refers to a mechanism which allocates scarce resources efficiently among competing users.

QUESTION #7

(a) What is meant by debt?

(b) List and explain three reasons how a country becomes indebted.

Majority of the candidates attempted this question and performed well. The candidates were expected to list and explain the following reasons:

(a) Financing capital intensive projects, (b) Importation of strategic commodities, (c) Borrowing from bilateral and multilateral donor agencies, (d) Increasing defense expenditures, (e) Deficit spending.

QUESTION #8

(i) What is meant by development? (ii) List three characteristics each of the third World countries and developed countries.

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This was one of the least attempted questions. The few candidates who attempted this question could not adequately explain what is development nor list the characteristics of countries in the third world and the developed countries. The candidates were expected to provide the following answers: Development refers to the general improvement in the various segments of a people , or a group of people in a living condition. Characteristics of countries in the third world:

(a) High population growth rate; (b) High unemployment rate; (c) A large number of the population relies on subsistence farming; (d) Poor infrastructure; (e) Low per capita income. Characteristics of developed countries: (a) High per capita income; (b) Skilled labor force; (c) Well developed infrastructure; (d) Self sufficient in food production; (e) Technological advanced.

QUESTION #9

Indentify and explain four major sources of government revenue.

This was a popular question which was attempted by majority of the candidates. The candidates’ responses were orderly presented .

14 The candidates were expected to indentify and explain the following Sources:

(a) Taxation,; (b) Dividend and profits from state enterprises; (c) Fees ,fines, and licenses; (d) Grants; (e) Loans.

QUESTION #10 What are externalities?

This was one of the least attempted questions. The candidates were expected to provide the following answer: Externalities refer to effects, good or bad, imposed by the act of production, or

consumption, for which no price is charged.

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GEOGRAPHY 2

1. GENERAL COMMENTS

The paper compared favorably with that of the previous years and satisfied the demands of

the WAEC Syllabus. The composition of the question paper together with the contents was

very fair and the standard was within the reach of any candidate that was adequately

prepared for the examination. However, the over-all performance was below satisfactory.


Some candidates did exemplary work to prove their skills in the following areas:

(1) Orderly presentation of materials: Some of the candidates gave relevant points which

were orderly presented and developed into meaningful answers. They also related

their facts to questions set and discussed the validity of the points. There were also a

few instances where candidates were able to buttress their answers with relevant

examples:

(2) Artistic Skill: Few of the candidates demonstrated their artistic skills by presenting

well drawn, correctly labeled and inserted maps.


Candidates’ weaknesses were identified by their approach to questions and the answers they

presented:

(1) Disregard for Rubrics: Some candidates did not attempt the required number of

questions per section. Bulk of the candidates also answered more than one question

on the same page;

(2) Lack of Knowledge of the Subject Matter: Candidates’ inability to explain basic

geographical terms, concept and theories.

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(3) Weathering, chemical weathering etc, is a clear indication of the candidates’ lack of

knowledge of the subject matter;

(4) Poor Mathematical Skills: A good number of the candidates did not seem to be

mathematically prepared as shown by the deplorable performance in Question 2b;

(5) Inability to Understand the Demands of the Questions: Most of the candidates did not

care to find out requirements of the questions and ended up providing irrelevant

answers; and

(6) Brief Answers: It has become a common practice for candidates to give brief answers

by listing facts without explaining in detail.


Candidates should:

(1) be encouraged to adhere to the rubrics of the questions and have access to past

question papers;

(2) have access to several books to enhance their chances of passing the examination;

(3) properly go through the questions before responding to them;

(4) thoroughly read the questions, look for the trigger words and make sure they think

about the type of questions before answering them.

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5. DETAILED COMMENTS ON INDIVIDUAL

QUESTIONS

QUESTION #1 Study the map of Grand Kru County and answer the following questions:

(a) Calculate the area covered by the map in kilometer.

(b) State the approximate height of the trigonometrical station.

(c) State the direction of the flow of River Johloh, and calculate the distance

covered by the river in kilometers.

This compulsory question did not claim the attention of most of the candidates.

Few candidates who attempted it went off track.

Candidates were expected to measure the dimensions of the map (width and

length) and relate it to the map scale to obtain the actual length and width in

kilometer as indicated below:

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Data Map scale=1: 150000 Ground length=21.2km = km2.445

2

Map length= 14.1cm Ground ( Actual) width:

Map width=14 cm If 1cm= 150,000cm

Solution 14cm=x Procedure A x=150000x14

Ground (actual) length: x=100000

2100000

If 1 cm = 150,000cm x=21km 14.1cm=x Ground width=21km x=150,000x14.1 Area=length x width x=

100000

2115000cm

21.2km x 21km

x=21.15km

Procedure B

1cm to 100000

150000

1cm to 1.5km Ground length:

If 1cm=1.5km

14.1cm=x

X=14.1cm x 1.5km

X=21.2km

Ground width:

If 1cm=1.5km

14cm= x

X=14 x 1.5km

X=21km

Ground width = 21km

Area = length x width

21.2km x 21 km

= 445.2km 2

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QUESTION #2

Account for four geographical conditions that favor the production of hydro-electric

power.

This question did not attract most of the candidates and their performance was

unsatisfactory. It required the candidates to show the four geographical conditions that are

relevant for the production of hydro-electric power. Most of the candidates gave the

economic importance and problems of hydro-electric power. Candidates were expected to

provide the following answers:

Hydro-electric power is the power (energy) derived from moving water as it passes over a

waterfall or is released from behind a dam.

Geographic conditions that favor the production of hydro-electric power include:

(a) A steep gradient or slope to enable river or streams to plunge down swiftly to turn the

hydro turbines;

(b) Sufficient and constant volume of water;

(c) Heavy capital outlay;

(d) A large domestic and industrial demand for hydro-electric power;

(e) A regular supply of water;

(f) Suitable site for dam;

(g) The existence of lakes;

(h) Presence of waterfall; and

(i) Adequate high temperature against freezing of water

QUESTION #3

Explain in four ways by which chemical weathering differs from mechanical

weathering.

This question demanded that candidates explained four differences between chemical

weathering and mechanical weathering but the answers they provided had no link with the

question. For example “chemical weathering is when you use chemicals to improve your

weather and mechanical weathering is a system of weathering set by God”. “Chemical

weathering takes place in secondary industry”. Candidates were expected to provide the

following answers:

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Chemical weathering Mechanical weathering Chemical weathering involves decaying; Mechanical weathering involves

disintegration; Decomposition of rocks by chemical action the processes involved chemical of rocks and by physical action are solution, hydration, weathering temperature changes, frost action and carbonation; alternating wetting and drying and unloading;

Chemical weathering takes place on the exposed Mechanical weathering takes place surface of the rocks and inside the rock; on the exposed surface of the rocks; Rock minerals increase in size or unite Rock minerals do not increase in size nor with each other to form new minerals or unite with each other to form new dissolve during the process of chemical rocks; they dissolve during the process of weathering; mechanical weathering;

During the process of chemical weathering, During the process of mechanical the original rock minerals are changed to weathering original rock minerals do not

new chemicals . change to new chemicals.

QUESTION #4

(a) State three characteristics of longitudes.

(b) Calculate the latitudinal position of a car whose driver observes that GMT is

20:00 hrs, while the local time is noon.

This was a popular question and was answered by almost all of the candidates. Some of the

candidates were not able to calculate the longitudinal position of the car by using either the

linear (graphical) method or mathematical method. Few of the candidates were able to find

the time difference but could not convert it to longitude. Candidates were expected to

provide the following points as answers. They are:

(1) angular distances east or west of the Prime Meridian; (2) measured in degrees;

(3) imaginary lines running from north to south;

(4) used for calculating local time;

(5) measured up to 360⁰ (180⁰ W to 180⁰ E).

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(6) They have many great circles as any apposite pairs and makes a great circle;

(7) Green Meridian is their reference point.

(b) Solution GMT=20:00hrs

Driver’s local time=12:00 noon

Longitude of GMT= 0⁰

Longitude of driver= x

Time difference= 20:00hrs-12:00hrs

= 8hrs

If 1hr= 15⁰

8hrs= x

X=15x 8 = 120⁰ W

QUESTION #5

Name three countries in the world well noted for the cultivation of rubber. Explain

three main conditions that hinder the cultivation of rubber in one of the countries

named.

Part of this question was answered by a good number of candidates by naming countries like

Malaysia, Indonesia and Liberia etc. On the contrary, few candidates mentioned

countries such as USA, Japan, Senegal and Mauritania which had no place on the world

map of rubber production.

However, Question 5b was poorly answered by the candidates who, instead of giving the

factors that hinder rubber production, most of them responded by listing the importance of

rubber production to a named country.

Three countries in the world noted for the cultivation of rubber:

(a) i. Malaysia; ii. Indonesia; iii. Sri lanka; iv. India; and v. Liberia.

(b) The three main conditions that hinder the cultivation of rubber in one of the countries named:

i. Infertile soil;

ii. The land tenure system;

iii. Inadequate capital;

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iv. Inadequate skilled and unskilled labor;

v. Fluctuation of world marked price for rubber;

vi. Diseases and pests;

vii. Poor communication network;

viii. Increased demand for land for growing of food crops; and

ix. High cost of farming inputs.

QUESTION #6

What is meant by the term plantation agriculture?

Discuss four factors that influence the location of plantation.

This was a popular question but the candidates who answered it performed below expectation. A good number of the candidates gave the definition of plantation agriculture and buttressed their answers with examples of plantation farms in Liberia but they failed woefully to discuss four factors that influence the location of plantation farming. Candidates were expected to provide the following answers:

(a) Plantation agriculture is a system of commercial farming practiced in tropical and

sub-tropical countries. It involves the cultivation of large estates of land with a single

crop such as cocoa, rubber, tea, coffee etc.

(b) Four factors that influence the location of plantation agriculture include

i. Suitable climate;

ii. Fertile soil;

iii. Availability of large market to consume the produce;

iv. The nature of the relief;

v. Availability of cheap skilled and unskilled labors;

vi. Availability of good transport net-work;

vii. Availability of capital; and

viii. Land tenure system.

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QUESTION #7

Account for five remedies of overpopulation.

Candidates were expected to give the remedies of over population. Some candidates did not

understand the question. They presented facts responsible for rapid population growth and

the consequences of rapid population growth.

Answers of few candidates who were on the right track were limited to mere listing of facts.

Candidates should have provided these points:

i. Birth control through family planning measures;

ii. Increase in food production;

iii. Migration;

iv. Limiting the sizes of towns;

v. Provision of gainful employment for women;

vi. Discouraging early marriages;

vii. Sex and mass education;

viii. Legalization of abortion;

ix. Encouragement of monogamy;

x. Stiffening immigration laws; and

xi. Raising school entering and leaving ages.

QUESTION #8

On an outline map of Liberia, mark and name:

i. Two areas where coffee is mainly produced;

ii. Explain three conditions that favor its production.

This question demanded a sketched map of Liberia showing two named areas of coffee

production, example Voinjamin (Lofa County), and COCOPA (Nimba County). Maps

presented were poorly drawn. There were no titles and outlying features. Above all, coffee

producing areas were wrongly marked; areas such as Monrovia and Tubmanburg were

marked by some candidates as coffee producing areas.

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For question 8b, a good number of the candidates only listed the conditions that favor coffee

production but failed to explain them. Candidates were expected to respond to the questions

as follow:

(a)

(b) The three conditions that favor the coffee production include:

i. A mean monthly temperature of about 23⁰ C with a minimum daily

temperature of 15⁰ C;

ii. Rich, deep and well drained soils;

iii. Annual rainfall of about 1100mm-1780 mm;

iv. Frost free climatic zone;

v. A cool dry season;

vi. Shelter from winds;

vii. Abundant labor;

viii. Adequate capital;

ix. Good communication net work and

x. High demand for coffee.

25

QUESTION #10

On a sketch map of Africa, mark and name:

(a) i. Namib desert;

ii. Kalahari desert and iii. Sahara desert

(b) Outline three threats of desert to the inhabitants.

This question demanded the drawing of the map of Africa and showing Nimbi,

Kalahari and Sahara deserts. Maps were poorly drawn, without title and outlying

features. Very few candidates could outline the threats of desert to the inhabitants.

Candidates were to provide the following answers. Desert leads to:

a. (1) crop failure or poor yield of crops;

(2) displacement of people and settlements;

(3) shortage of water for animals and human consumption; It could:

(4) cause the loss of pasture of livestock;

(5) result in hot and dusty environment;

(6) affect serious farming activities;

26

It leads to:

(7) loss of vegetation;

(8) climatic change;

(9) loss of agricultural lands;

(10) famine and hunger and also lower the water table; and

(11) exposes the soil to wind erosion.

27

HISTORY 2

1. GENERAL COMMENTS

This paper compared favorably with those of previous years. It was within the scope of the

examinations syllabus and at the level of the candidates. All the questions in the paper were

clear, straightforward and simple. The general performance of the candidates was rather

unsatisfactory.


Generally, the candidates’ strengths were demonstrated in two areas:

(1) Logical Presentation of Facts - Candidates presented their answers in an orderly

manner; and

(2) Adherence to Rubric- Candidates responded to the questions according to the

instructions provided in the paper.


The following were identified as candidates’ weaknesses:

(1) Inadequate Knowledge -Some of the answers were vague;

(2) Inability to Comprehend and Interpret Questions-Candidates’ inability to understand

the demands of the questions led them to provide long and irrelevant answers to some

questions;

(3) Poor Communication Skills- There were numerous instances of misspelling,

grammatical errors and poor expressions which adversely affected the meaning of

what the candidates tried to write.


Candidates should:

(1) carefully read and analyze examination questions before writing their answers;

(2) prepare themselves fully for this exam by improving their reading and comprehension skills so that they can satisfy the demands of the questions;

28

(3) change their lukewarm attitude or approach towards the subject;

(4) engage in constant reading of past examination papers


QUESTION #1

Describe monarchy government as relates to traditional Liberia.

This question was very popular and was attempted by most of the candidates who mentioned

the essential points as required by the question. The question demanded that candidates

provided the following answers: Monarchy, as a form of government, is based on hereditary

rule headed by a king or queen; whereas in traditional Liberia, the government was headed

by a chief.

QUESTION #2 Account for two causes of the Twin Battle of 1822.

Many candidates attempted this question and highlighted some of the relevant answers.

Candidates should have mentioned that the Twin Battles were fought because of the failure

of the colonists to pay the natives the balance money for the land they purchased on

December 15, 1821; and also some of the natives did not favor the sale of the land.

29 QUESTION #3

Discuss three advantages and disadvantages of a unitary state.

This question was also attempted by most of the candidates who treated it satisfactorily.

Candidates mentioned the advantages of unitary a state as it operates a unicameral legislature

and central government is supreme. Some outlined the following advantages as the president

appoints government officials who serve at the will of the president; and that power of the

government is given to a single authority.

QUESTION #4 Name and explain three major means through which the colony of Liberia expanded.

This question was popular, and it was attempted by a vast majority of the candidates.

Candidates indicated that the three means by which the colony of Liberia expanded were:

i. Direct purchase - colonial leaders made direct purchase of land from the indigenous

people;

ii. Voluntary annexation - the indigenous voluntarily gave their land to the colony to be

under the protection of the government of Liberia; and

iii. Force-was also employed in areas where the indigenous people were unwilling to sell

their land to the settlers.

QUESTION #5

Describe the development and effect of European trade in West Africa.

This was a popular question attempted by majority of the candidates; however they did not

answer it properly. Candidates should have mentioned that trade in commodities started

between the Europeans and Africans after the arrival of the Europeans. They traded in

commodities for exports such as: slaves, ivory and pepper features; and imports were cloths,

beads, cowries and iron rods. The Portuguese introduced coastal trade to the coastal peoples

of West Africa who became middlemen in the trade with the hinterland. Africans from the

interior settled along the coast in city-states such as Elmina, Accra, Bonny, Opobo and

Calabar. The Portuguese left a permanent influence in West Africa. They named Cape

Palmas, Sierra Leone, Cape Verde, Lagos, Cameroons; etc.

30

QUESTION #6

Account for five achievements of Sonni Ali.

This question was very unpopular and it was attempted by few of the candidates who did not

treat it satisfactorily.

Candidates should have indicated that the achievements of Sonni Ali included the following:

i. He turned Songhai into an empire by conquests;

ii. established a strong state with a powerful army and navy;

iii. divided the empire into provinces; and appointed provisional governors.

QUESTION #7

Explain five contributions of geographical factors to the history of West Africa.

This question was attempted by few candidates whose answers were not the demands of the

question.

Candidates should have given the answers as follow:

(i) That the grassland area of West Africa is a rich agricultural region producing a variety of

crops;

(ii) the open grassland made communication and trade easy within Western Sudan;

(iii) the thick tropical forest of West Africa made penetration in the interior of West Africa

inaccessible for the Europeans; and

(iv) the Niger River was the cradle of the empire in the Western Sudan.

31

QUESTION #8

Name the four river valleys in which civilization first emerged and three ways in which

they encouraged the development of civilization.

This question was attempted by very few candidates who were unable to provide the answer

satisfactorily.

Candidates were expected to provide the following points:

Valley of the:

i. Nile river- in Egypt;

ii. Tigris and Euphrates rivers- in Asia ;

iii. Indus river- in India and

iv. Yellow river- in China

The rich soil of the river valleys encouraged farming, the establishment of city-states and

writing.

QUESTION #9

Account for four differences between direct and indirect rules of European colonies in Africa.

This question was attempted by few candidates who failed to provide the correct demands for the question. The question demanded that candidates provided the following answers as indicated below: i. Direct rule was administered by the British;

ii. Indirect rule was administered by the French;

iii. Under the indirect rule local chiefs had authority over their settlements and

iv. Under the direct rule local chiefs had no authority over their settlements.

32

QUESTION #10

Discuss four main characteristics that separated man from animals during the Stone

Ages.

This question was attempted by few candidates who did not mention the relevant points.

The candidates should have mentioned that man had the ability to:

(i) exchange ideas;

(ii) the ability to use tools and weapons;

(iii) the ability to establish permanent settlements;

(iv) and engage in agricultural activities.

33

LITERATURE-IN-ENGLISH 2

1. GENERAL COMMENTS

The questions were within the scope and standard of the candidates and compared favorably

with those of the pervious years. The questions, vocabularies and literary terms were within

the standards set in the regulations of the syllabuses of the Ministry of Education and

WAEC. The general performance of the candidates was not commendable because their

weaknesses overshadowed their strengths.


Most of the candidates demonstrated adherence to the rubrics. No candidate attempted more

than the required number of questions and none of them wrote with pencil. Besides, there

was improvement in penmanship. Few candidates demonstrated understanding of the

questions.

3. CANDIDATES’WEAKNESSES

Unfortunately, few candidates demonstrated understanding of the questions.

Most of them demonstrated poor skills in the following:

(1) Ideas were incoherent and disorganized;

(2) There were poor grammatical usage, wrong spelling, diction and punctuation;

and trite expressions;

(3) They also lacked knowledge of some of the prescribed texts.

(4) They failed to address the demands of the questions most of which were not

answered fully; and

(5) Candidates lacked knowledge of poetry analysis and poetic devices.


It was observed that the poor performance of some candidates resulted from lack of

knowledge of the prescribed texts, and the lack of basic writing skills and knowledge of

literary terminologies. Therefore the following are recommended:

34

(1) Private candidates should make efforts to obtain copies of and be familiar with all of

the prescribed texts for Literature-in-English.

(2) Private and Re-sitter candidates should hire the services of professional Literature

teachers to tutor them and help them improve their writing and literary skills.

(3.) Candidates should make use of the Chief Examiners’ Reports and past WAEC question papers.


SECTION A - DRAMA

AFRICAN DRAMA

Ola Rotini: THE GODS ARE NOT TO BLAME

QUESTION #1

Describe activities in the play “The Gods Are Not to Blame” that make the title

appropriate.

The prescribed text is popular and available in the schools. A large number of the candidates

attempted the question with poor results. Those that attempted the questions did not address

the issue of the appropriateness of the title to the activities. They lacked the ability to use

proper descriptive words to describe the activities and relate them to the title.

They could have referred to these activities;

(1) Odewase’s encounter with the “Old Man” and the events leading to

the death of the Old Man who turned out to be his father.

(2) Odewale’s temperament as described by Baba Fakunle: “Your hot

temper like a disease is the curse that brought you trouble.”

(3) Odewale realized after his downfall that the Gods should not be blamed because he

was responsible for his own downfall by allowing himself to be used.

35

QUESTION #2

Considering the two major kinds of dramas, comedy and tragedy, explain in which

category would you place “The Gods Are Not to Blame”?

This question was attempted by a large number of candidates. The result was fair as most of

the candidates were able to place it in the proper category of tragedy. However, most of them

were unable to state why. This indicated that they could not identify tragic incidents such as:

The killing of King Adetusa by his son Odewale; the suicide of Queen Ojuola and the

blindness and self-banishment of King Odewale.

Ama Atta Aidoo: THE DILEMMA OF A GHOST

QUESTION #3

Describe the reaction of Nana to the news that her grandson had married a “white

woman”.

Few candidates attempted this question. Their attempt was a complete failure as it

demonstrated their lack of knowledge of the text and their limited descriptive vocabulary.

Nana demonstrated the attitude of repulsion, surprise and disappointment over the news.

According to her this act was abominable and against their tradition.

QUESTION #4

With reference to the text, “The Dilemma of a Ghost”, explain the African views on

child bearing and barreness.

Because of their lack of knowledge of the text, the few candidates who attempted this

question used their personal views and experiences instead of reference to the text. Poor

spelling, sentence construction and grammar were common in their explanation.

36

Child bearing was viewed as a necessary aspect of marriage and barrenness was a taboo.

This was portrayed when Nana instructed Eulalie to undergo “stomach washes” to enable her

to have a child.

NON-AFRICAN DRAMA

Bernard Shaw: ARMS AND THE MAN

QUESTION #5

Describe the character of Nicola in light of Louka’s criticism.

Few candidates attempted this question with poor results. Candidates lacked understanding

of the question and knowledge of the text.

Nicola regarded Louka as stupid, complacent and lacked ambition. He however remained

faithful to her.

QUESTION #6

Identify and discuss one type of humor used in the play.

No candidates attempted the question which indicated that they were not au courant with the

text. The play displayed an extravagant exhibition of humor, For example, Captain

Bluntschilli who should be ready for battle would prefer chocolate to live ammunition. He

was referred to as” Chocolate cream soldier”.

Oliver Goldsnith: SHE STOOPS TO CONQUER

QUESTION #7

Describe the first encounter between Tony Lumpkin and the party of Charles Marlow.

Few candidates attempted this question with satisfactory results. There were glaring lack of

knowledge of the text, incoherence and trite expression of facts.

37

Tony Lumpkin was regarded as a mere composition of tricks and mischief. He played a fast

trick on Charles Marlow on their first encounter by directing him to his house under the

pretence that it was an inn.

QUESTION #8

Describe the case of the missing jewelry and the disappointment of Mrs. Hardcastle

over her son Tony.

The case of the missing jewelry was one of the popular humor in the play. Few candidates

attempted this question with fair success. This indicated their understanding and

appreciation of humor in the drama.

Candidates were able to describe briefly the case of the missing jewelry but not the

disappointment of Mrs. Hardcastle over her son’s behavior.

SECTION B - PROSE

AFRICAN PROSE

Elechi Amadi: THE CONCUBINE

QUESTION #9

With reference to the text, compare and contrast the characters of

Agwoturumbe and Anyika.

This question was attempted by a few candidates. The novel, though prescribed, seemed not

to have been read by most private candidates. Those who attempted the questions could not

show the similarities and differences in characters between the two medicine men.

Similarly, both of them discovered that Ihuoma was considered the wife of the sea-god who

inflicted suffering and death on mortal men who attempted to have a love affair with her.

In contrast, Agwoturumbe claimed to have the power to bind the sea –god through a

sacrifice. On the other hand Anyika concealed it was impossible to accomplish this feat.

38

QUESTION #10

Discuss the author’s treatment of predestination and the existence of the supernatural

in the novel.

The few candidates who attempted the question did not follow its demands. They seemed

unfamiliar with the text; as a result, they did not answer the question appropriately.

Anyika and Agwoturumbe, the two medicine men, mentioned that Ihuoma was from the

spirit world and was the wife of the sea –god who was one of the

controllers of human destiny. She was destined to cause death and suffering on any mortal

man who desired her.

Wilton Sankawolo: THE RAIN AND THE NIGHT

QUESTION #11

With reference to the text, describe the ceremonies of the Seating of the new chief.

Although the novel was written by a Liberian and has a local setting, many private

candidates seemed not to be familiar with the text. The candidates who attempted the

question did so dismally. They did not refer to activities in the novel but rather used their

personal experience. They also failed to use proper descriptive words to describe the dancing

and feasting during the ceremonies.

QUESTION #12

Compare and contrast the leadership of Gbolokai and Kortuma.

The few candidates who attempted this question failed woefully. They were incapable of

showing similarity and difference in the two leaderships. They simply narrated events.

Both chiefs, Gbolokai the father and Kartuma the son ruled the people of Fuama village at

different periods. They loved and respected their people.

Gbolokai, the father, used the counsel of older men during his leadership and was able to

prevent war with other villages. His son, Kartuma used a younger generation of men in his

government who did not compromise or negotiate; as a result there was a terrible war

between the people of Fuama and Golaland during his leadership.

39

NON-AFRICAN PROSE

George Orwell: ANIMAL FARM

QUESTION #13

Describe the battle of the Cowshed and its effect on the lives of the animals.

Although Animal Farm has become the most popular non-African novel in schools; many

private candidates are unfamiliar with the technicalities embedded in the narrative. Many

candidates attempted the question with fair results.

The battle was the result of Mr. Jones’ determination to repossess his farm from the animals.

This resulted to a furious fight between Mr. Jones’ group of humans and the animals. The

animals, having won the battle, became more vigilant and determined to prove their ability to

maintain the farm.

QUESTION #14

Discuss the amendments made in the original seven commandments of the animals.

How did this portray the characters of the pigs?

A good number of candidates who attempted the question did fairly well in discussing the

amendments but failed to indicate how it portrayed the characters of the pigs.

The amendments were made in the 5

th and 7

th commandments thus:

(1). No animal shall drink alcohol (in excess).

(2). All animals are equal (but some are more equal than others).

40

Daniel Defoe: ROBINSON CRUSOE

QUESTION #15

Explain why Crusoe was referred to as Governor of the island.

Very few candidates attempted the question with poor results. The text is not popular among

candidates because they have not read it. Their responses indicated that they were unfamiliar

with the content.

Crusoe was marooned on an uninhabited island for twenty-eight years. He was finally able

to board a ship and return home to England. He decided to return to the island to assist the

new inhabitants. Thus he earned the title of Governor.

He regarded this reference as appropriate and with pride.

QUESTION #16

Describe the moments of regrets and repentance as experienced by Crusoe as he lived

on the Island.

No candidate attempted this question.

Crusoe suffered many moments of regrets such as loneliness, illness, hunger, cannibalistic

activities by savages, etc. He repented and was able to overcome these sufferings

SECTION C - POETRY

QUESTION #17

With reference to the poem “Abiku”, describe family life in the Delta.

Few candidates attempted this question. Their responses were based on their personal

experience rather than reference to the poem.

“Abiku” is a name given to children believed to be of the spirit world who are involved in a

cycle of birth and death.

Families of the Delta who believe in these “Abikus” mark their bodies when they die to

identify them when they return or to prevent them from returning.

41

QUESTION #18

Describe the various poetic device used in the poem, "Ulysses

No candidate attempted this question. It has been observed that candidates lack the

knowledge of various poetic devices; they therefore shy away from such questions.

The poet made use of poetic devices such as metaphor, simile, personification,

onomatopoeia, etc. The poem is written in blank verse.

QUESTION #19

Describe the style used by the poet to develop the poem “Is My Team Ploughing?”

No candidate attempted the question. The poem is written in the form of a dialogue

between a man and his dead friend to indicate the relationship between the living and the

dead.” The poetic devices used include irony, hyperbole, metonymy etc.

QUESTION #20

Describe the various images used by the poet to indicate his strong emotional

attachment to his motherland in the poem, “We Have Come Home”.

No candidate attempted this question which obviously indicated they were unfamiliar with

the content.

The poem emphasized the rural setting with predominantly visual and auditory imageries.

42

MATHEMATICS 2

1. GENERAL COMMENTS

The paper was of the standard required. It covered 75% of the syllabus and was graded by a

systematic marking scheme. Unfortunately, majority of the candidates employed wrong

methods towards the solving of problems. It is apparent that majority of the candidates that

sat this exam were ill-prepared.


Candidates’ strengths were exhibited in the following areas:

(1) They exhibited their skills in problem solving factorizing algebraic expressions and simple substitution of algebraic expressions; and

(2) observed the proper use of mechanical signs (plus, minus, etc.) in related working

areas/problems.


The general weaknesses of the candidates were summarized as follow:

(1) Candidates lacked the ability to translate verbal problems into mechanical problems;

(2) Candidates’ response to questions involving coordinate geometry, trigonometry and

plane geometry was very poor.

(3) Majority of the candidates failed to adhere to the rubrics of the paper by attempting to

answer more than one question on a page.


In order to help minimize to a considerable degree the above stated weaknesses, the

following have been suggested:

(1) that Chief Examiners’ Reports be used as a guide for candidates preparing to sit the

December Examination;

(2) that candidates should not only use WAEC past questions for study purposes, but also stick

to the rubrics of the examinations; and

43

(3) that WAEC takes absolute responsibility of reminding or encouraging candidates

to attend tutorial classes.


QUESTIONS

QUESTION #1

(a) The Gbotoes invested part of $7000.00 at 4% and the remainder at 5%. Their

annual income from the two investments was $330.00. Find the amount they

invested at each rate.

(b) (i) Solve: .

(ii) Find the reciprocal in standard form of 3 .

(a) Few candidates attempted this question, apparently due to their inability

to interpret and transform it into a workable system; those that attempted it got the

answer in a way that is not consistent with related method.

Solution: Let $x be the investment at 4% $(7000 – x) will be invested at 5%

Income from both investments

i.e. Hence $ was invested at 4% and $ was invested at 5%

(a)(i) Majority of the candidates were attracted by this problem. The problem appears

very simple. A major default exhibited was squaring both sides of the equation to

get rid of the exponent. There was also a problem of obtaining the square root of

both sides.

Solution (bi):

Hence, is the only solution to this equation.

44

(ii) This question appeared very unfamiliar. Most of the candidates

attempted it but the concept of complex numbers seemed very

remote.

Solution (bii): 3 has conjugate 3

Hence

QUESTION #2

(a) Simplify the following:

(i)

(ii)

(b) If find x.

(a)(i) This question was very popular. Majority of the candidates

attempted it. Nearly all those that attempted it lacked the simple systematic

method of doing division, multiplication, subtraction and division involving

algebraic expressions/ fractions in that order.

Solution (i):

45

(ii) Many of the candidates were fascinated by this question. Factorization of the quadratic

expression was well executed. The only eminent problem was manipulation of the

negative sign to enhance cancellation.

Solution (ii):

(b) This was not a popular question. The candidates who attempted it performed poorly.

Solution :

QUESTION #3 (a) If

(b) The seventh term of a geometric progression is 256 and the first term is 4. Find the fifth term.

This question was very popular and attractive. Majority of the

candidates got the exact solution. Solution:

but

Hence

46

Very few candidates attempted this question, apparently due to lack of related concept between ratio and common difference, most of them got confused.

Solution: but and Hence

QUESTION #4

(a) The vertices of a rectangle have coordinates .

Find the measure of the perimeter of the rectangle.

(b) Find the area of the rectangle.

(a) Only very few candidates attempted this question perhaps due to its geometric nature. Those that attempted it made use of the distance formula. Solution:

(-5,1) (4,1)

X (-5,-3) (4,-3)

Using the distance formula we find the distance between (-5,1) and (4,1) is 9 units (the length of the rectangle) and the distance between (-5,1) and (-5,-3) is 4 units (the width of the rectangle). The points (-5,-3) and (4,-3) could be used to find the length as well as the points (4,-3) and (4,1) for the width.

47 The perimeter of any rectangle is , where l is the length and w is the width. Hence, the perimeter of the given rectangle is 2(9 + 4) = 36 units

(a) Same details as that of question (4a).

Solution: or (length times the width)

QUESTION #5 What is the value of x in the diagram below given that are tangent segments to the circle? B

G x

D

H I

This question was very strange to the candidates. Nearly all of them did not attempt it. The

few that attempted it took a different approach that was a complete variance to geometric

concepts.

Solution:

QUESTION #6 (a) Evaluate given that

(b) Prove that

58°

48

(a) This question appeared simple and very altruistic. Candidates

that attempted executed a very successful substitution thus leading to the

desired result.

Solution:

(a) This question was not well-liked. Majority of the candidates did not attempt it perhaps due to its technical mathematical analysis.

Solution: To show LHS = RHS =

LHS:

Hence, LHS = RHS

QUESTION #7

The probability that a man will live 10 more years is , and the probability that his

wife will live 10 more years is .

Find the probability that

(a) both will be alive in 10 years,

(b) at least one will be alive in 10 years,

(c) neither will be alive in 10 years.

Majority of the candidates attempted this question. The concept of independent events was meaningfully manifested.

Solution:

(a

49

(b)

(c)

50

BIOLOGY 2

1. GENERAL COMMENTS

The standard of the paper compared favorably with those of previous years. The questions

were straightforward and should have been within reach of average candidates. Candidates’

performance however, was below expectation; only a few who actually showed signs of

adequate preparation were able to score marks above average.

2. CANDIDATES' STRENGTHS

Candidates' strengths was exhibited in their answers to questions #2(a), (b) and #3 wherein

they answered the questions properly exhibiting their firm grasp on those aspects of human

biology.


The following are weaknesses that were observed:

(1) Spelling of scientific words still remains poor;

(2) Diagrams were badly drawn and labeled;

(3) Provision of non- detailed answers to questions;

(4) Poor understanding of demands of the questions; and

(5) Improper allocation of time- wasting time on some questions to the detriment of

others.

51


In order to ensure that the overall standard of candidates writing the exam be improved, the

following recommendations are forwarded for due and timely consideration:

(1) that candidates purchase copies of the past examination papers and Chief Examiners’

Reports to aid them during the period that they are preparing for the exam;

(2) that candidates must learn how to allocate time appropriately to questions and how to

answer questions effectively;

(3) that candidates read scientific documents extensively to improve their horizon,

diction and spelling abilities; and

(4) that they also take pains to prepare well in advance for the examination.


QUESTION #1

(a) What is a microscope?

(b) (i) Make a large labeled diagram (8-10cm long) of a compound

light microscope.

(ii) List and state the functions of the three types of microscopes

used by forensic scientists for examining evidence.

Candidates provided poorly drawn diagrams that did not represent a microscope. They

listed the types of microscopes but were unable to state the functions of the various types.

The correct answers to the questions are as follow:

(a) A microscope is any device that enables us to see details in an object by enlarging it.

52

(b)(i)

DIAGRAM OF A LIGHT MICROSCOPE

(ii) The three types of microscopes and their functions are as follow:

(1) Light microscope: used to begin the examination of

evidence;

(2) Scanning electron microscope(SEM): used to take

pictures of the surface of extremely small objects, like

grain of sand or pollen; and

(3) Comparison microscope: this type of microscope allows

forensic scientists to compare small objects, such as

bullets, side by side.

53

QUESTION #2

(a) In a tabular form, list four different types of cells found in man and give a

function for each.

(b) (i) Name the two types of cell divisions.

(ii) Give two examples each of life processes involved in each type of the cell

divisions listed above.

(c) Describe the process of fertilization in:

(i) Mammals; and (ii) Dicots.

Most candidates responded well to these questions but some performed poorly in answering

the (c) portion where they were requested to describe the process of fertilization in mammals

and dicots. The correct answers to the questions are as follow:

(a) Any four of the following would be accepted.

(b) (i) Meiosis

-formation of sperm/egg

-formation of pollen grain/ovule

(ii) Mitosis

-formation of new cells in the Malphigian layer of the skin

-healing of wounds by binary fission

CELL

FUNCTION

(i)Nerve cells Transmit impulses/messages from nerve fibers

(ii)Muscle cells Form muscles for movement, attachment of bone, give shape to the body

(iii)Red blood cells Perform circulatory/excretory/respiratory/ transport functions; carry O2 to the body; remove Co2 from cells

(iv)Sperm cells For reproduction/ fertilization

(v) White blood cells Defend/protect the body/immunity

(vi) Epidermal cells Protects the body against diseases or germs/infection/dehydration

(vii)ova/egg cells For reproduction

(viii)bone cells

/osteoblasts Form bones/give support, aid movement/give shape to the body

(ix)rods Photoreceptor in dim light

(x)cone Photoreceptor in bright light

54

-production of RBC and WBC in bone marrow

-cell division in liver

-growth

-spermatogenesis

(c) (i) Fertilization in Mammals

Fertilization is preceded by copulation or sexual intercourse. This process

involves the union of gametes that are formed in special organs called gonads.

The male gametes called spermatozoa (sperm) are produced in the testes by a

process known as spermatogenesis. The female gametes called ova or eggs

are produced in the ovary by a process called oogenesis. Eggs are non-motile,

but sperms are specialized for movement. When sperm are released by the

male, their flagella beat rapidly, pushing them along in all directions. As they

approach the egg,they encounter a chemical called fertilizin released by the

egg. Fertilizin stimulates the sperm to move faster and aids in the attachment

to the surface of the egg. When the sperm makes contact with the egg, the

acrosome releases enzymes that dissolve an opening through the protective

membrane of the egg. Once the head of the sperm enters the egg, the tail

remains outside. The sperm is now joined to the egg to form a zygote. This

process is called fertilization.

(ii) Fertilization in Dicots

When a pollen grain is transferred to the stigma, it absorbs a sugary fluid

secreted by the stigma and increases its volume. The exine finally bursts open

and the intine grows out into a long narrow tube called the pollen tube.

The generative nucleus divides into two nuclei called the male gametes. The

pollen tube grows into the ovule through the micropyle as it reaches the

embryo sac, the pollen tube discharges its contents. One of the male gametes

fuses with the egg cell to form a zygote and this is known as fertilization. The

primary endosperm nucleus also undergoes repeated divisions to produce

nutritive endosperm. The whole ovule becomes a seed while the ovary

becomes the fruit.

55

QUESTION #3

(a) (i) Describe three features of a typical vertebra.

(ii) Name three types of skeletons found in mammals and in each case

name one animal which possesses it.

(b) (i) State four functions of the mammalian skeleton.

(ii) Name three types of joints found in the mammalian skeleton.

This question was popular with the candidates given the way they satisfactorily responded to

it. Most candidates were able to provide the perfect responses to them. The correct answers

to the questions are as follows:

(a) (i) A typical vertebra contains the following:

(Any three of the following would be accepted)

- neural canal - This is for the passage of the spinal cord.

- neural spine - This projects upward dorsally for the attachment of

muscles.

- centrum - A solid piece of bone below the neural canal that

provides support and protection for the spinal cord. It

carries the neural arch and neural spine.

- transverse process - they project from the sides of each vertebra

for attachment of muscle to ligament.

- facets of zygapophysis - are small projections from the neural arch

that articulates the adjacent vertebrae.

(ii) The three types of skeletons found in animals and the animals in which

they are found are as follows :( Any three of the following would be

accepted)

- exoskeleton- insects

- endoskeleton- man

- hydrostatic skeleton(body fluid) -earthworm

- Chitin(exoskeleton)-cockroaches(insects);crayfish

- Cartilage-sharks, rays

56

The mammalian skeleton performs the following functions:

(Any four of the following would be accepted)

(b) (i) - provides: (1) support and form(shape);

- (2) protection for delicate organs;

- (3) a surface to which muscles are attached;

(4) a storehouse for minerals and fats; and

- (5) manufactures red blood cells and certain

white blood cells.

Three types of joints found in mammalian skeleton are listed below: (Any three of

the following would be accepted)

(ii) - ball-and socket joints;

- hinge joints;

- pivot joints;

- gliding/sliding joint;

- fixed /immovable joint.

QUESTION #4

(a) List the four steps of Koch’s postulates

(b) Name a viral disease that infects each of the following organisms: (i) human;

(ii) plants; and

(iii) cows.

Question #4 was very unpopular with the candidates. Most of them failed to list the steps

involved in the Koch’s postulates. Others could not distinguish which viral disease affects

the various organisms and in so doing failed to answer the question properly. The correct

answers are as follow:

(a) The four steps of Koch’s Postulates are as follow:

(1) The suspected disease-causing microorganism should always be found in the

animal with the disease.

(2) The microorganism must be isolated from the diseased animal and grown in

pure culture.

(3) When microorganisms taken from the pure culture are injected into a

healthy, susceptible animal, they must cause the disease.

(4) The microorganisms must be isolated from the experimentally infected

animal and grown in pure culture again, and it should be identified as the

same organism isolated in step 2.

57

(b) Viral diseases that affect each of the following organisms are as follow: (Any one

of the following of each would be accepted):

(i) human-polio, chickenpox, measles, influenza, common cold, AIDS,

hepatitis;

(ii) plants-cassava mosaic,swollen root(cocoa), tobacco mosaic; and

(iii) cows- rinder pest/foot and mouth disease,

cowpox (mad cow disease).

QUESTION #5

(a) Define each of the following:

(i) Ecosystem;

(ii) Population; and

(iii) Ecological succession of plants.

(b) List four ways in which nitrogen can be made available to the soil for plant

growth.

Candidates answered part (a) of this question satisfactorily but were unable to favorably

answer part (b) which required them to list ways that nitrogen can be available to the soil

for plant growth, thereby losing a lot of valuable points. The correct answers to the

questions are as follow:

(a) (i) Ecosystem - a natural unit consisting of living(biotic) and non-

living (abiotic) elements interacting to produce a stable system;

(ii) Population - the total number of individuals of one species of

organism living in a particular habitat;

(iii) Ecological succession of plants - the establishment of series of

plant communities in a particular habitat, over a period of time

eventually resulting in the establishment of a climax community.

(b) Nitrogen can be made available to the soil for plant growth by the following:

(Any four of the following would be accepted.)

(i) symbiotic nitrogen fixation; (ii) application of nitrogen-containing fertilizers;

58

(iii) activity of nitrifying bacteria;

(iv) electrical/ lightening discharge in the atmosphere; (v) non-symbiotic nitrogen fixation; (vi) animals waste; and (vii) decaying nitrifying bacteria.

QUESTION #6

(a) Name and describe the two main types of leaves.

(b) Explain how leaves exchange gases with the environment.

(c) Describe the structure of a leaf viewed in cross section.

Of all the questions asked of the candidates, this was the worst because majority of them

failed to answer all the various subsections of this question. It can be deduced that

candidates are only bent on reading the zoological aspect of biology and not the botanical

aspect. The correct answers are as follow:

(a) (i) Simple leaf: has one blade and one petiole.

(ii) Compound leaf: has many blades and many petiole.

(b) Exchange of gases between the leaf and the environment takes place through the

stomata. During the day, carbon dioxide enters the leaf through the pores of the

stomata and is used for photosynthesis. Oxygen also enters the pores for the process

of respiration. The products of photosynthesis; water vapor and oxygen exit through

the stomata. However, the stomate opens to the needs of the leaf and is regulated by

specialized cells called guard cells.

(c) A leaf’s upper epidermis is covered by cuticle and contains stomata. The stomata

allow exchange of CO2 and O2 between the internal tissues of the leaf and the

environment. The guard cells, a kidney-shaped cell regulates the opening and closing

of the stomata. The layer below the epidermis is called the mesophyll, the site for

photosynthesis. The mesophyll contains two types of thin-walled cells:

(i) Palisade mesophyll - the upper portion filled with chlorophyll; and

(i) Spongy mesophyll - the portion which contains fewer chloroplasts with

intercellular air spaces. Within the spongy mesophyll are vascular tissues that

are composed of veins. The veins are surrounded by a sheet of parenchyma

that helps regulate the flow of materials into and out of the vascular tissues.

59

CHEMISTRY 2

1. GENERAL COMMENTS The paper compared favorably with those of previous years. It was directly drawn from the

Examination Syllabus and the National Curriculum of the Ministry of Education. The

questions were within the capabilities of the candidates. Generally, the performance of

candidates was below average.


The candidates’ strengths were noticed as follow:

(1) They showed or demonstrated a clearer understanding of the basic concepts of

electronic configuration of elements; and

(2) A slight understanding of the rudimentary concepts of organic Chemistry was also

observed as strength of candidates.


The candidates generally displayed weaknesses in the following areas:

(1) Candidates showed their glaring inability to prepare solution using volumetric

analysis concept.

(2) Their lack of understanding of laboratory concepts, which was evidenced by their

ignorance in demonstrating or illustrating diagrams, was vividly observed.

(3) Their lack of comprehension of stoichiometric relationships established between

reactants and reactants on the one hand, and reactants and products on the other hand

was clearly seen.

4. SUGGESTED REMEDIES Being cognizant of the following weaknesses demonstrated by the candidates, the following

suggestions are being advanced for future improved performance of candidates:

(1) The enhancement of the teaching of Chemistry in Liberian schools should be

channeled by the setting up of Science Laboratories in the various schools.

(2) Competent and qualified teachers be encouraged to accept assignments in rural areas

to upgrade the performance of rural candidates.

(3) All schools should not only be compelled to obtain copies of the Examination

Syllabuses before being permitted to register their candidates but also to obtain

copies of the Chief Examiners’ Reports to guide them on topics omitted by teachers

this will enable them face future challenges.

60

5. DETAILED COMMENT ON EACH QUESTION

QUESTION #1 Describe the preparation of the following solution. (a) 1.00 dm3 of 3.00 M NiCl2 (b) 2.50 x 102 cm3 of 0.00200M Cd(IO3)2 [Ni = 58.69, Cl = 35.45, I = 126.0, O = 16.00]

A few candidates attempted this question. Quite interestingly, out of this insignificant number, none exhibited or displayed the ability to answer this question correctly. Their inability would be largely attributed to their inadequate knowledge of content and how to express solutions to problems. Concentrations using molarity, molality and normality: Their prior knowledge and full comprehension of volumetric analysis could have compensated their performance.

The correct answer to the question should have been (a) Mol NiCl2 = MxV

=(3.00mol/dm3)x(1.00 dm3) = 3.00 mol Molar mass of NiCl2 =(58.69) + 2(35.45) = 126. 59 g/mol

Mass of NiCl2 = mole x molar mass = (3.00 mol)x (129.59 g/mol) = 388.77 g NiCl2

Therefore weigh 388.77 g of NiCl2 , dissolve it in a small volume of water and then add enough water to make 1.00 dm3 of solution.

(b) Mol Cd (IO3)2 = 2.5 x 102 cm3 x 1dm3/103 cm3x 0.002mol/dm3

= 0.0005 mol Cd(IO3)2

Molar mass of Cd(IO3)2 = 112.4 + 2(126) + 6(16) = 462.2 g/mol Mass of Cd(IO3)2 = (0.0005mol) x (462.2 g/mol) = 0.2311 g

Therefore weigh out 0.2311 g of Cd(IO3)2 , dissolve it in a small volume water and add enough water to make a volume of 250 cm3 of solution.

61

QUESTION #2 In a tabular form, give at least four (4) properties of the following: Solutions, colloids and suspension.

Few candidates attempted this question and their responses were generally unsatisfactory. The candidates apparently seemed not to have a vivid understanding of the distinction amongst the types of mixtures and inadvertently affected their performance on this question. Henceforth, the candidates would not list the properties.

The correct answer to the question is:

Property Solution Suspension colloids

Appearance Clear transparent and homogeneous

Cloudy, heterogeneous, at least two phases visible

Cloudy but uniform and homogeneous

Particle size Molecular or ionic in size, smaller than in suspensions and colloids.

Larger than in solutions or colloids

Larger than in solution but smaller than in suspension

Effect of Light (Tyndall affect)

No effect . Light passes through, no reflection.

Variable, may or may not scatter light

Light is disperses or scattered by particles

Sedimentation Particles do not settle out. They remain dissolved.

Particles will eventually settle out

Particles do not settle out; they remain suspended

QUESTION #3 Equilibrium is defined as a state of balance. Chemical equilibrium is a dynamic

equilibrium involving chemical changes. Consider the reaction below describing a chemical equilibrium involving hydrogen gas and iodine gas to form hydrogen iodide.

H2(g) + I2(g ) 2 HI(g), using acquired knowledge about chemical equilibrium,

show that Keq = [HI]2

[ I2] [H2 ]

62

A significant number of the candidates attempted this question and on the average, their articulations were very poor. Many of those candidates who attempted this question lacked the

manipulatory skills in deriving the chemical equilibrium constant from the reaction provided. Perhaps an adequate knowledge on chemical equilibrium would have aided or assisted their ability to answer the question.

The correct answer to the question is: H2(g) + I2(g) 2HI(g)

Keq = [HI]2

[ I2] [H2 ]

In the reaction, the rate of the forward reaction is: Rf = Kf[ I2] [H2 ]

And the rate of the reverse reaction is: Rrev = Krev[HI]2

At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction. Therefore, Rf = Rrev hence, Kf[ I2] [H2 ]= Krev[HI]2 but,

Kf = Keq = [HI]2 Krev [ I2] [H2 ] And Keq = [HI]2 [ I2] [H2 ]

QUESTION #4

The reaction between oxalic acid ( H2C2O4) and sodium hydroxide (NaOH) can be

described by the following reaction:

H2C2O4 (aq) + NaOH(aq) Na2C2O4(aq) + H2O(l)

(unbalanced) [H=1.00, Na= 23.00, C= 12.00, O= 16.00]

Calculate the concentration of the oxalic acid solution if it takes 0.034 L of a 0.200 M

NaOH solution to consume the acid in a 25.00 mL sample of this acid solution.

63

A few of the candidates attempted this question; generally their responses were not

impressive. Many of those who attempted it displayed weakness in the balancing of the chemical equation and expressing or establishing stoichiometric relationships between reactants and products. A significant number of them did not even have the slightest idea of rightly writing or stating the chemical formula for determining the molarity.

The correct answer to this question should be:

H2C2O4 (aq) +2 NaOH(aq) Na2C2O4(aq) +2 H2O(l) Mole of NaOH = MxV = (0.200mol/L)(0.034L) = 0.0068 mol

Mole of H2C2O4 = ½ mol NaOH from the balanced equation = ½(0.0068mol) = 0.0034 mol

Molarity = mol H2C2O4

Volume of solution = 0.0034mol 2.5 x 10-3 L = 0.136 M

QUESTION #5 Diamond and graphite are allotropic forms of carbon.

(a) Give one physical property of each. (b) Give two uses of each. (c) State one evidence that shows that both diamond and graphite are allotropic forms of carbon.

64

Majority of the candidates attempted this question and generally their responses were fairly good. Few of them could not give the evidence that reveals that both diamond and graphite are allotropic forms of carbon.

The correct answer to this question is.

Graphite Diamond

Physical properties

Very soft; low melting point; low density

Hardest material, high melting point, high density

Uses Used in pencils for writing, used as electrode in electrolysis, used as lubricant

Used in Jewry, used in drilling tools, used in cutting tools

Proof that it is an allotrope of carbon

Burns in excess oxygen to form carbon dioxide as the only product

Burns in excess oxygen to form carbon dioxide as the only product.

QUESTION #6 How many isomers does C4H10 have?

(a) Draw these isomers (b) Write a balanced equation for combustion of C4H10.

Few of the candidates attempted this question, but only an insignificant number answered the first part of the question quite satisfactorily. The part of the question which included (a) with focus on writing the isomers was inadequately done with candidates illustrating their glaring inability to write the isomers and neither part (b), which also revealed weaknesses on the part of the candidates to write combustion reaction for alkanes.

A prior adequate knowledge of organic Chemistry on isomerism and reaction of alkanes

could have compensated their ability to favorably answer or tackle the question.

The correct answer to the question is:

(a) C4H10, butane has two isomers.

CH3 H H H C C C H

H H H

65

H H H H H C C C C H H H H H

(a) C4H10 + O2 CO2 + H2O

2 (C4H10 +13/2 O2 4 CO2 + 5 H2O) 2C4H10 + 13O2 8 CO2 + 10 H2O

QUESTION #7 State the difference between radiation and radioactivity.

(a) Given that a certain radioactive substance is placed in a protective shield (lead block) to direct the movement of the radioactive emission, draw a completely labeled diagram of this radioactive emission. (b) Discuss the basic characteristics and behavior of the three rays emitted by the radioactive substance in an applied electric field.

An insignificant number of the candidates attempted this question. Their responses to this question were generally unfavorable. They could not explicitly distinguish between radiation and radioactivity.

Part (a) of the question also could not be tackled by most of the candidates. Their inability

was perhaps precipitated by their none exposure to the rudimentary concepts of nuclear chemistry.

This implied that instructors of Chemistry should dedicate some of the time to the teaching of nuclear Chemistry.

The correct answer to this question is:

Radioactivity refers to the process in which one nucleus (element) changes into a different nucleus (element) or the spontaneous breakdown of an atom by emission of particles and / or radiation.

Radiation refers to the transmission o f energy through space in the form of particles and/

or waves.

66

A completely labeled diagram of radioactive substance placed in a lead block with emission influenced by an applied electric field.

Alpha (α) radiations consist of a stream of alpha particles. They are in the form of

helium nuclei. They have a charge of +2, they are attracted toward the negative plate in applied electric field and are deflected away from a magnetic field. They have a very low penetrating power and very high ionizing potential.

Beta (β) radiations consist of a stream of electrons; they have a charge of -1. They are attracted toward the positively charged electric field. They are deflected by a magnet field, they fairly good penetrating power and lower ionizing potential.

Gamma (γ) radiation is energy in the form of electromagnetic radiation. They contain no particles, hence no charge. They are unaffected by electric or magnetic field. They have very high penetrating powers and very low ionizing power.

67

QUESTION #8 Each of the following represents the end of an element’s electronic configuration. For

each, tell which period and group the element is in, identify the element and state whether the element is a metal, a nonmetal, or a metalloid.

(a) 3s23p2 (b) 5s24d2 (c) 4s23d7 (d) 3s23p6 (e) 3s23p5 (f) 3s23p3 [ Si = 14, Zr = 40, Co = 27, Ca= 20, Cl = 17, S= 15]

The correct answer to this question should be. Configuration Period Group Identity(symbol) description

(a) 3s23p2

3 IV A Silicon, Si metalloid

(b) 5s24d2

5 IVB Zicronium, Zr metal

(c) 4s23d7

4 VIIIB Cobalt, Co metal

(d) 3s23p6

3 VIIIA Argon, Ar nonmetal

(e) 3s23p5

3 VIIA Chlorine, Cl nonmetal

(f) 3s23p3

3 VA Phosphorus, P nonmetal

Question # 9

Draw and state the function(s) of the below listed laboratory apparatus: Erlenmeyer flask, beaker, burette, pipette, separatory funnel, watch glass, condenser, wash bottle, triple beam balance, thermometer, test tube, and graduated cylinder. Few of the candidates attempted this question and their responses were generally poor. They demonstrated their inability to diagrammatically illustrate or portray these laboratory apparatus. This implies that, even in the absence of elaborate laboratory facility of setups, instructors of Chemistry should seek the opportunity to expose the candidates to the

exhibition of common laboratory apparatus and their functions.

68

69

PHYSICS 2

1. STANDARD OF THE PAPER

The general standard of the paper compared favorably with those of previous years. The

questions were not only set at the level of the candidates but were also consistent with the

demands of the Physics Examinations Syllabus. The questions were clearly set for the

comprehension of the candidates.


The strengths were exhibited in their ability to define basic physical terms.


Candidates’ were unable to:

(i) follow the rubrics to the questions;

(ii) translate simple physical principles into meaningful formulae to solve problems;

(iii) use the metric prefixes for simple conversion of units and

(iv) perform simple mathematical manipulations.


To remedy these weaknesses, candidates of this Examination should attend

intensive tutorial classes before attempting the examination.


QUESTIONS

QUESTION #1

a) List four advantages of mercury-in-glass thermometer over alcohol-in-glass

thermometer

b) State the conditions required for a body to be in stable equilibrium under the action

of two or more parallel forces.

This question, being compulsory, was attempted by nearly all of the candidates. However,

their responses were highly discouraging. In the first part, the candidates interchanged the

advantages of the two kinds of thermometers.

70

For the second part, only few of the candidates could give at least one of the conditions

required for a body to be in a stable equilibrium under the action of two or more parallel

forces.

The desired answers are as follow:

(a) Four advantages of a mercury-in-glass thermometer over an alcohol-in-glass

thermometer are:

Mercury:

(i) does not wet glass but alcohol tends to cling to the glass wall of the thermometer;

(ii) is opaque and so easily seen but alcohol does not;

(iii) has a regular expansion than alcohol;

(iv) responds to slight change in temperature because of its high conductivity but

alcohol does not.

(b) The conditions required for a body to be in a stable equilibrium under the action of two

or more parallel forces are:

(i) The algebraic sum of all the forces acting on the body must be zero; that is, the sum

of all the forces acting in one direction must be equal to the sum of all the forces

acting in the opposite direction;

(ii) The sum of all the clock-wise moments (torques) must be equal to the sum of all the

anti-clockwise moments.

QUESTION #2

(a) Convert 15m/s to km/h.

(b) Calculate the values of x and y in the nuclear equations below.

14

N + 4He→

yO +

1H

X 2 8 1

This question was also a compulsory one and was attempted by majority of the candidates

who could not provide the correct conversion in the first part. The candidates’ performance

on this part of the question clearly indicated their lack of knowledge of the basic metric

prefixes; thus most of them were unable to change meter to kilometer.

The second part of the question was poorly treated by the candidates. Their overall

performance showed that they have no knowledge of Nuclear Physics.

71

The expected solutions and answers are as follow:

(a) Solution

Conversion factors: 1km = 1000m

1hr = 60 min.

1min. = 60 sec.

15m/s x 60sec./1min. x 60min./1hr x 1km/1000m

= 15x3600x1km/1000hr

= 54000km/1000hr

= 54km/hr

(b) The values of x and y in the nuclear equations

(i) X + 2 = 8 + 1

X + 2 = 9

X = 9-2

X = 7

(ii) 14 + 4 = y +1

18 = y+1

Y = 18-1

Y = 17

QUESTION #3

a) Explain the terms

(i) Mass

(ii) Weight

b) A block of ice of dimensions 2m by 2m by 1m has a mass of 40kg.

(i) Calculate its density.

(ii) If the block of ice is placed on a table, what is the maximum pressure it

exerts on the table?

This question, like questions 1 and 2 was a compulsory one and was also the most popular

question. Majority of the candidates correctly answered the first part of the question but

could not perform the mathematical manipulations to determine the maximum pressure the

block of ice can exert on the table.

72 The expected responses are as follow:

a) Mass: The mass of a body is the measure of the quantity of matter it

contains. The mass of a body is a scalar quantity and remains constant

irrespective of the location of the body above sea level.

Weight: The weight of a body is the measure of the gravitational force exerted on the

body. The weight of a body is a vector quantity and acts in the direction of the

gravitational pull. It varies with the location of the body.

DATA

Mss = 40kg

Volume = 2m x 2m x1m = 4m3

Force = weight =40kg x 10m/s2 = 400N

Minimum area = 2m x1m = 2m2

(i) Density = mass/ volume

= 40kg/4 m3

= 10kg/ m

3

(ii) Maximum Pressure = Force/Minimum area

= 400N/2 s2

= 200N/ s2 or 2

QUESTION #4

(a) Two resistors, R1 and R2 of resistances 4 and 6 respectively are connected in

parallel in a circuit and the load across the parallel combination is 12V

(iii) Draw a diagram of the circuit.

(iv) Calculate the total current in the circuit.

(v) Calculate the equivalent resistance of the parallel combination.

(b) Define the following:

(vi) Dew point

(vii) Center of gravity

(viii) Heat capacity

Almost all of the candidates attempted this question though it was optional. Most of them,

however, .drew series circuit instead of parallel circuit which demonstrated their ignorance

of simple electrical circuits. Few candidates drew the appropriate circuit diagram and

performed the calculations required.

The second part, which was definitions, was poorly attempted.

73 The expected solution and answers are as follow:

(i) Circuit diagram

The total current in the circuit is the sum of the individual current in each resistor. That is,

IT= I1+I2+I3.

I1 = V/R1 = 12v/4Ω -3A

I2 = V/R2 = 12v/6 Ω = 2A

Thus, IT = 3A =4A =5A

(i) 1/Req =1/R2 or Req = R1 x R2/R1 + R2

Req = (4x6) Ω/(4+6) Ω = 24/10 =2.4 Ω

(ii) Dew point is the temperature at which the water vapor in the atmosphere is

just sufficient to saturate it.

(iii) Center of gravity is the point in a body where the resultant weight of the body

tends to act.

(iv) Heat capacity is the quantity of heat required to raise the temperature of a

body by one degree.

74 QUESTION #5

A particle is projected upward with an initial velocity vo at an angle Ө with the ground.

Deduce a mathematical expression to compute the following: [ Sketch a diagram of the

projectile motion.]

(i) The horizontal and vertical components of the initial velocity (vo);

(ii) The maximum height (Hmax);

(iii) The range (R).

(iv) Given the initial velocity of the particle is 100m/s and the angle of projection is 30º,

what is the time taken to attain maximum height?

The unpopularity of the question among the candidates clearly indicated that projectile

motion is not taught in almost all of the schools though it is in the National Curriculum and

the WAEC Physics Syllabus.

The expected solutions and answers are as follow:

Diagram of projectile motion

(i) Horizontal and vertical components of the initial velocity

Horizontal component: Vox = VoCosθ

Vertical component: Voy = VoSinθ

(ii) Time taken for the particle to attain maximum height

At maximum height, the final velocity (vf) of the particle is zero.

75 For upward displacement, the acceleration due to gravity is –g.

Now using the equation: vf = voy + gt, we have vf = voy –gt but vf = 0

Hence, 0 = voy – gt

gt=voy

t=voy/g but voy=vosinθ, thus, t=vosinθ/g

For maximum height,

S=voyt -1/2gt2 but voy=vosinθ and t=vosinθ/g we now have

S=Hmax=(vosinθ)(vosinθ/g) – 1/2g(vosinθ/g)2

Vo2sin

2θ/g – g/2(vo

2sin

2θ/g

2)

Vo2sin

2θ/g – Vo

2sin

2θ/g

(2vo2sin

2 θ – vo

2sin

2θ)/2g

Hmax= (vo2sin

2θ)/2gs

(iii) The range of the particle in projectile motion is the horizontal distance from the point

of projection to the point where the particle strikes the ground.

Note: the total time taken by the particle from the point of projection to where it falls is

twice the time it takes to attain maximum height.

That is, total time (T)=2t.

Using the equation: s=R=voxT + gT2/2, we have

R=(vox)(2t) +g(2t)2/2 but vox=vocosθ, t=vosinθ/g and g=0 (horizontally)

Hence, R=2vocosθ(vosinθ/g) + 0(2)(vosinθ/g)2

R=2vo2sinθcosθ/g + 0

R=2vo2sinθcosθ/g or R=vo

2sin2θ/g since2sinθcosθ=sin2θ

(iv) Data

Vo=100m/s

θ=30º

t=?

t=vosinθ/g

=100m/ssin30 º/10m/s2

=100m/s(0.5)/10m/ s2

t =5sec.

76

QUESTION # 6

(a) During a breakdown along the Robert’s Field Highway,, a driver lifted his car

weighing 2200Nwith a screw jack of efficiency 40%. If the handle of the screw

jack 35cm long and the pitch of the screw is 0.5cm;

(i) What is the velocity of the machine?

(ii) What force did the driver apply at the end of the handle to lift the car?

(b) What is reflectance?

Like question 5, this question was not popular with the candidates. Very few of them

attempted and answered the second part(3b) correctly.

These are the solutions and answers expected.

Data

Pitch(p)=0.5cm

L=F=2200N

Eff.=40%

r=35cm

V.R=?

E=?

(i) V.R=2πr/p

V.R=2(3.14)(35cm)/0.5cm

V.R=439.6

(ii) Eff.= (M.A/V.R) x 100%

40%=(M.A/439.6) x 100%

40/100=(M.A/439.6) x 100/100

100M.A=17584

M.A=175.84

Note: M.A=L/E → E=L/M.A

E=2200N/175.84

E=12.51N

Reflectance is the ratio of the light reflected from a surface to the light falling on the

surface.

77

QUESTION # 7

(a) List the two basic concepts of the kinetic theory of matter.

(b) How does the speed of sound vary with the

(i) density of an elastic material? (ii) Temperature of an elastic material?

(c) Account for three factors that determine the amount of light reflected by the

surface of a reflecting body.

Majority of the candidates poorly answered this question; however, a few of them provided

the correct answers.

The expected answers are as follow:

The two basic concepts of the kinetic theory of matter are:

(1) The molecules of a substance are in constant motion; the motion depends on the

average kinetic energy of the molecules.

(2) Collisions between molecules of matter are perfectly elastic (except when chemical

changes or molecular excitation occur).

The speed of sound in an elastic material varies inversely as the reciprocal of the square

root of the density of the material.

The speed of sound in an elastic material varies directly as the square root of the absolute

temperature of the body.

The amount of light reflected by the surface of a reflecting body depends on:

(1) The nature(kind) of material underlying the reflecting surface;

(2) The smoothness of the surface and

(3) The angle at which light strikes the surface.

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