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INSPIRATION FOR THE BEGINNERS BARRACKPORE 9748058100 Page 1

SOUND

Q1. Put in ascending order of speed of sound in the mediums I-Water, II-Steel, III-Nitrogen-

निम्ननिखित माध्यम I-जि , II-स्टीि , III- िाइट्र ोजि-में ध्वनि की गनत को आरोही क्रम में व्यवखथित करें .

(a) III, II, I

(b) III, I, II

(c) I, III, II

(d) II, I, III

Show Answer

Ans.(b)

Sol. The speed of sound is different for different type of mediums. The speed of sound is maximum

in solids while minimum in gases. The speed of sound in air at normal temperature and pressure is

322m/s. The speed of sound depends on the density of the medium through which it is travelling.

The medium which has higher density, the sound will travel faster in that medium.

Q2. In which medium the speed of sound is maximum at a temperature of around 20°C?

नकस माध्यम में ध्वनि की गनत अनिकतम 20 निग्री सेखियस के तापमाि पर अनिकतम होती है?

(a) Air / वायु

(b) Granite / गे्रिाइट्

(c) Water / जि

(d) Iron / िौहा

Show Answer

Ans.(d)

Sol. The speed of sound depends on the elasticity and density of the medium through which it is

travelling. Greater the elasticity and lower the density, sound travels faster in that medium. At

temperature of 20°C, the speed of sound is maximum in iron.

Q3. Sound waves-



ध्वनि तरंगे-

(a) Can travel in vacuum/ वैकू्यम में यात्रा कर सकती हैं

(b) Can travel only in solids / केवि ठोस में यात्रा कर सकती हैं

(c) Can travel only in gases. / केवि गैसो ंमें यात्रा कर सकती हैं

(d) Can travel both in solid and gaseous medium./ ठोस और गैसीय मध्यम दोिो ंमें यात्रा कर सकती हैं.

Show Answer

Ans.(d)

Sol. Sound waves need to travel through a medium such as a solid, liquid or gas. The sound waves

travel through each of these mediums by vibrating the molecules in the matter. The molecules in

solids are packed as tightly as solids, and in gases they are very loosely packed. The spacing of the

molecules, enable sound to travel much faster through solid than gases, So sound waves can travel

in solid, liquid and gaseous medium.

Q4. The walls of the hall, built for music concerts should-

हॉि की दीवारो,ं संगीत संगीत काययक्रमो ंके निए कैसा बिाया जािा चानहए-

(a) Amplify sound / पररवनियत ध्वनि

(b) Transmit sound / ध्वनि संचार

(c) Reflect sound / प्रनतनबंनबत ध्वनि

(d) Absorb sound / अवशोषण ध्वनि

Show Answer

Ans.(d)

Sol. The walls of the hall built for music concerts should absorb sounds. Most of the solid walls

reflects the sound. If the walls of concert hall reflect the sound, then audiences hear the echo sound.

So to avoid this, there is a need to built soft surface walls.

Q5. To hear a clear echo, the minimum distance between the reflecting surface and the observer

should be-

एक स्पष्ट गंूज/ प्रनतध्वनि सुििे के निए, प्रनतनबंनबत सतह और पययवेक्षक के मध्य नू्यितम दूरी होिी चानहए-

(a) 165 feet / 165 फीट्



(b) 165 metre / 165 मीट्र

(c) 16.5 feet /16.5 फीट्

(d) 16.5 metre /16.5 मीट्र

Show Answer

Ans.(d)

Sol. The repetition of sound produced due to the reflection from a large surface like wall, hill or

mountain is called echo. Consider an observer is producing a sound and it gets reflected by an

obstacle. The sound travel towards the observer and the observer hear the sound again. Let d be the

distance between the observer and the obstacle, v is the sound velocity and t is the time taken by

the sound to and fro motion, then the velocity of the sound is given by

V= 2d/t

Velocity of sound is given by, V = 2d/t

Where t = time taken by the sound for to and fro motion.

Substituting t = 1/10 sec, it is minimum time required to distinguish between two sounds

V = velocity of sound = 330 m/sec

at 20° C

then d=Vt/2=1/2 [330×(1/10)]

= 16.5 m

Q6. The velocity of sound in air is approximately-

वायु में 0 निग्री सेखियस पर ध्वनि की गनत िगभग________ होती है.

(a) 10 km/sec. / 10 नकमी / सेकंि

(b) 10 mile/min. / 10 मीि / नमिट्

(c) 330 m/sec. / 330 मीट्र / सेकंि

(d) 3×1010 /sec. /3 × 1010 / सेकंि

Show Answer



Q7. Two astronauts cannot hear each other on the moon’s surface, because-

चंद्रमा की सतह पर दो अंतररक्ष यात्री एक-दूसरे को िही ंसुि सकते हैं, क्योनंक-

(a) Their ears have stopped working on the moon / उिके काि चंद्रमा पर काम करिा बंद कर देते है

(b) No atmosphere on the moon / चंद्रमा पर कोई वातावरण िही ं

(c) They wear special space suits on the moon / वे चंद्रमा पर नवशेष अंतररक्ष सूट् पहिते हैं

(d) The sound travels much more slowly on moon / चंद्रमा पर ध्वनि बहुत िीरे-िीरे यात्रा करती है

Show Answer

Ans.(b)

Sol. In order for sound to propagate from one place to another, it requires a medium or a fluid to

move through. The air on the earth allows sound waves to move from one point to another.

However, there is vacuum on surface of moon. Thus, there is no sound on the moon.

Q8. Consider the following statements:

निम्ननिखित कििो ंपर नवचार करें :

1. A flute of smaller length produces waves of lower frequency. / एक छोट्ी िंबाई की बांसुरी कम आवृनि

की तरंगें पैदा करती है.

2. Sound travels in rocks in the form of longitudinal elastic waves only. / ध्वनि केवि अिुदैध्यय िोचदार

तरंगो ंके रूप में चट्टािो ंमें यात्रा करती है.

Which of the statements given above is/are correct?

ऊपर नदए गए कििो ंमें से कौि सा सही है/ हैं?

(a) 1 only / केवि 1

(b) 2 only / केवि 2

(c) Both 1 and 2 / 1 और 2 दोिो ं

(d) Neither 1 nor 2 / िा तो 1 िा ही 2

Show Answer

Ans.(b)

Sol. A flute of long length produces the waves of higher wavelength(λ) and lower frequency(v), thus

a flute of smaller length produces waves of higher frequency(v) and lower wavelength(λ) . Therefore

statement 1 is not correct. Sound is a longitudinal wave. Transmission of sound in any medium is



only possible by longitudinal waves. Thus, sound travels in rocks, in the form of longitudinal wave.

Longitudinal waves are the waves in which the displacement of the medium is in the same direction

as or the opposite direction to the direction of travel of the wave. Thus statement 2 is correct.

Q9. Consider the following statements about ultrasonic waves:

अल्ट्र ासोनिक तरंगो ंके बारे में निम्ननिखित कििो ंपर नवचार करें :

1. They can destroy insects / वे कीड़ो ंको िष्ट करते है.

2. They can clean clothes by removing dust / वे िूि को हट्ाकर कपड़े साफ कर सकते हैं

3. They can be used to treat disease / वे बीमारी ठीक करिे के निए प्रयोग की जाती है.

4. They can control automatic doors / वे स्वचानित दरवाजो ंको नियंनत्रत करते है.

Of the above statements

उपरोक्त कििो ंमें से -

(a) 1 and 2 are correct / 1 और 2 सत्य है

(b) 3 and 4 are correct / 3 और 4 सत्य है

(c) 1, 2 and 3 are correct / 1, 2 और 3 सत्य है

(d) All are correct / सभी सत्य है

Show Answer

Ans.(d)

Sol. Sound waves are longitudinal-mechanical wave. Sound waves are divided into three categories

that cover different frequency range; Audible wave (20 Htz- 20,000 Htz), Infrasonic waves (20,000 Htz). Ultrasonic waves are used to destroy insects, clean clothes by

removing dust, treat diseases, control automatic doors, detection of aircraft and submarine,

determination of depth of sea etc.

Q10. Ultrasonics are sound waves of frequency

अल्ट्र ासोनिक ध्वनि तरंगो ंकी आवृनि _________हैं.

(a) Greater than 20,000 Hz /20,000 हट्टयज से अनिक

(b) Less than 10,000 Hz / 10,000 हट्टयज से कम



(c) Equal to 1000 Hz /1000 हट्टयज के बराबर

(d) None of these / इिमे से कोई िही ं

Show Answer

Ans.(a)

Sol. Sound waves are longitudinal-mechanical wave. Sound waves are divided into three categories

that cover different frequency range; Audible wave (20 Htz- 20,000 Htz), Infrasonic waves (20,000 Htz). Ultrasonic waves are used to destroy insects, clean clothes by

removing dust, treat diseases, control automatic doors, detection of aircraft and submarine,

determination of depth of sea etc.

Q11. A biotechnique in which ultrasonic sound is used-

एक बायोटे्खिक नजसमें अल्ट्र ासोनिक ध्वनि का उपयोग नकया जाता है -

(a) Sonography/सोिोग्राफी

(b) E.C.G / ई.सी.जी

(c) E.E.G / ई.ई.जी.

(d) X-ray/एक्स-रे

Show Answer

Ans.(a)

Sol. Sonography or ultrasonography is an important mean of clinical diagnosis. It is a diagnostic

imaging technique based on the application of ultrasound. It is widely used in the field of medical

science. It is mainly used to provide a variety of information about the health of the mother during

pregnancy, and the health and development of embryo or foetus.

Q12. Bats can fly during dark nights and also prey. This is because-

चमगादड़ अंिेरी रात के दौराि उड़ सकता है और नशकार भी कर सकता है. क्योनंक -

(a) The pupil of their eyes is large/उिकी आंिो ंकी पुतिी बड़ी होती है

(b) Their night vision is very good/उिकी रात की दृनष्ट बहुत अच्छी है

(c) Every birds can do this/हर पक्षी यह कर सकता हैं



(d) They produce ultrasonic waves and are guided by them./वे अल्ट्र ासोनिक तरंगो ंका उत्पादि करते हैं

और उिके द्वारा निदेनशत होते हैं.

Show Answer

Ans.(d)

Sol. Bats are a fascinating group of animals. They are one of the few mammals that can use

ultrasonic sound to navigate. As they fly, make an ultrasonic (shouting) sound. The returning echoes

give the bats information about anything that is ahead of them, including the speed and size of an

insect and which way it is going. This system of finding prey is called echolocation-locating things by

their echoes.

Q13. Which one of the following is the effect of the flight of supersonic jet?

निम्ननिखित में से क्या सुपरसोनिक जेट् की उड़ाि का प्रभाव है?

(a) Air pollution/वायु प्रदुषण

(b) Eye disease/िेत्र रोग

(c) Depletion in ozone layer/ओजोि परत में कमी

(d) None of these/इिमे से कोई िही ं

Show Answer

Ans.(c)

Sol. A jet engine is a machine for turning fuel into thrust. The thrust is produced by action and

reaction also known as Newton’s third law of motion. The force (action) of the exhaust gases

pushing backward produces an equal and opposite force (reaction) called thrust, that powers the

vehicle forward. Those jet planes which are able to fly faster than the speed of sound are called

supersonic jet planes. Jet engines are responsible for depletion of ozone. Flying at stratosphere

height, they emits nitrogen oxide which has the potential to destroy significant quantities of ozone

in the stratosphere.

Q14. Decibel unit is used to measure-

िेसीबि यूनिट् नकसे मापिे के निए उपयोग नकया जाता है -

(a) Light intensity / हल्की तीव्रता

(b) Sound intensity / ध्वनि तीव्रता

(c) Magnitude of Earthquake / भूकंप की तीव्रता



(d) None of the above / उपरोक्त में से कोई िही ं

Show Answer

Ans.(b)

Sol. ‘Decibel’ is used to measure the intensity of sound in atmosphere.

Q15. As per the WHO, the safe noise level for a city is-

WHO के अिुसार, एक शहर के निए सुरनक्षत आवाज़ स्तर नकतिा है -

(a) 45 db

(b) 50 db

(c) 55 db

(d) 60 db

Show Answer

Ans.(a)

Sol. As per the WHO the safe noise level for a city is 45 decibel (db).

ENGLISH OWS

Q1. Free from difficulties (a) Eloquence (b) Extricate (c) Ewe (d) Dodo S1. Ans.(b) Q2. A dramatic performance (a) Masque (b) Matins (c) Cosmocrat (d) Bronco S2. Ans.(a) Q3. A person who loves art (a) Philatelist (b) Jibe (c) Philomuse (d) Lamster S3. Ans.(c)



Q4. Shot remaining end of cigarette (a) Stub (b) Hebetude (c) Chthonic (d) Epigram S4. Ans.(a) Q5. A flower which is star shaped (a) Slough (b) Aster (c) Garrison (d) Conjuror S5. Ans.(b) Q6. A bad-tempered person (a) Splenetic (b) Gust (c) Goose (d) Choppy S6. Ans.(a) Q7. Not to be considered serious (a) Draper (b) Derisory (c) Harridan (d) Heifer S7. Ans.(b) Q8. Country under the protection of a more powerful country. (a) Protectorate (b) Scrimmage (c) Scurry (d) Hireling S8. Ans.(a) Q9. A rich, creamy soup typically made with shellfish. (a) Purgative (b) Bisque (c) Capsize (d) Lope S9. Ans.(b) Q10. A line of animals or slaves fastened or driven along together. (a) Curmudgeon (b) Coffle (c) Cortege (d) Patrilineal S10. Ans.(b) Q11. A person who is slow to learn (a) Emblazon



(b) Gillie (c) Hag (d) Dunce S11. Ans.(d) Q12. Customs and habits of a particular group. (a) Mores (b) Mendicant (c) Reveille (d) Seer S12. Ans.(a) Q13. Take great pleasure (a) Stevedore (b) Revel (c) Subpoena (d) Rattle S13. Ans.(b) Q14. One who lives cheaply and spends little (a) Scrimp (b) Trousseau (c) Soprano (d) Truss S14. Ans.(a) Q15. A thin and homeless child (a) Velodrome (b) Drover (c) Waif (d) Wrath S15. Ans.(c) TIME AND WORK

Q1. A can build a wall in 15 days and B can build it in 10 days, while C can completely demolish the wall in 12 days. If they start working at the same time, in how many days will the work be completed?

A एक दीवार को 15 ददन में बना सकता है और B इसे 10 ददन में बना सकता है, जबदक C इसे 12

ददन में पूरी तरह बबााद कर सकता है. यदद वे समान समय पर काया करना शुरू करते हैं तो, काया

दकतने ददनो ों में पूरा होगा?

(a)13 (b)12 (c)14 (d)16



Q2. If A can do a work in 10 days and B can do the same work in 15 days, then how many days will they take to complete the work both while working together?

यदद A एक काया को 10 ददन में और B उसी काया को 15 ददन में पूरा कर सकता है, तो वे दोनो ों

एकसाथ काया को पूरा करने में दकतना समय लेंगे?

(a)7 (b)8 (c)6 (d)9

Q3. ‘A’ completes a work in 12 days. ‘B’ completes the same work in 15 days. ‘A’ started working alone and after 3 days B joined him. How many days will they now take together to complete the remaining work?

‘A’ एक काया को 12 ददन में पूरा करता है. ‘B’ उसी काया को 15 ददन में पूरा करता है. ‘A’ अकेले

काया करना शुरू करता है और 3 ददन बाद B उस से जुड़ता है. अब शेष काया को पूरा करने के

दलए उन दोनो ों को दकतना समय लगेगा?

(a)9 (b)8 (c) 6 (d) 5

Q4. Machine A can print one lakh books in 8 hours. Machine B can do the same job in 10 hours. Machine C can do the same job in 12 hours. All the three machines start job at 9.00 am. A break down at 11.00 am and the other two machines finish the job. Approximately at what time will the job be finished?

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मशीन A 8 घोंटे में एक लाख बुक चाप सकती है. मशीन B उसी काया को 10 घोंटे में पूरा कर सकती

है. मशीन C उसी काया को 12 घोंटे में पूरा कर सकती है. सभी तीन मशीन 9.00 पूवााहन पर काया

करना शुरू करती है. 11पूवााहन पर मशीन A को बोंद कर ददया जाता है और शेष दो मशीन काया

पूरा करती हैं. लगभग दकतने बजे काया समाप्त होगा?

(a) 12.05 noon (b) 1.30 pm (c) 1.05 pm (d) 11.30 am

Q5. 12 men complete a work in 18 days. Six days after they had started working, 4 men joined them. How many days will all of them take to complete the remaining work?

12 पुरुष एक काया को 18 ददन में पूरा करते हैं. छ: घोंटे बाद उन्ोोंने काया करना शुरू दकया. 4

पुरुष उनसे जुड़ते हैं. शेष काया को पूरा करने में उन सभी को दकतना समय लगेगा?

(a) 10 days (b) 12 days (c) 15 days (d) 9 days

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Q6. 5 men can prepare 150 toys in 5 days working 6 hours a day. In how many hours 10 boys can prepare 200 toys in 10 days, if a man works thrice as fast as a boy?

5 पुरुष ,5 ददन में 6 घोंटे काया करते हुए 150 खखलौने बना सकते हैं. यदद एक पुरुष एक लड़के की

तुलना में तीन गुना कुशल है, तो 10 लड़के 10 ददन में दकतने घोंटे काया करते हुए 200 खखलौने बना

सकते हैं?

(a)6 (b)7 (c)8 (d)9

Q7. 12 men and 16 boys can do a piece of work in 5 days. 13 men and 24 boys can do the same work in 4 days. How long will 7 men and 10 boys take to do the same work?

12 पुरुष और 16 लड़के एक काया को 5 ददन में पूरा कर सकते हैं. 13 पुरुष और 24 लड़के उसी

काया को 4 ददन में कर सकते हैं. उसी काया को करने में 7 पुरुष और 10 लड़कोों को दकतना समय

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लगेगा?

(a)10 (b)20 (c)30 (d)40

Q8. A and B can do a work in 45 and 40 days respectively. They began the work together, but A left after some time and B finished the remaining work in 23 days. After how many days did A leave?

A और B एक काया को क्रमश: 45 और 40 ददन में पूरा कर सकते हैं. वे एकसाथ काया करना शुरू

करते हैं , लेदकन कुछ समय बाद A काया छोड़ देता है और B शेष काया को 23 ददनो ों में पूरा करते

हैं. A ने दकतने ददनो ों बाद काया छोड़ा था?

(a)9 (b)10 (c)11 (d)12

Q9. Sanjeev can build a wall in 20 days and Parveen can demolish the same wall in 30 days. If they work on alternate days with Sanjeev starting the job on the 1st day, then in how many days will the wall be built for the first time?

सोंजीव एक दीवार को 20 ददन में बना सकता है और परवीन उस दीवार को 30 ददनो ों में बबााद कर

सकता है. यदद वे वैकखिक ददनो ों पर काया करते हैं और पहले ददन सोंजीव काया की शुरुआत करता

है, तो पहली बार दीवार दकतने ददनो ों में बनेगी?

(a)115 (b)114 (c)113 (d)119

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Q10. A is 30% more efficient than B. How much time will they, working together, take to complete a job which A along could have done in 23 days?

A, B की तुलना में 30% अदिक कुशल है. वे दोनो ों एक साथ एक काया को पूरा करने में दकतना

समय लेंगे दजस काया को A अकेले 23 ददन में पूरा कर सकता है?

(a) 11 days (b) 13 days (c) 20(3/17) days (d) None of these

Q11. A can build up a wall in 8 days while B can break it in 3 days. A has worked for 4 days and then B joined to work with A for another 2 days only. In how many days will A alone build up the remaining part of wall?

A एक दीवार को 8 ददन में बना सकता है जबदक B इसे 3 ददन में तोड़ सकता है. A, 4 ददनो ों के दलए

काया करता है और दिर B उस से जुड़ता है और केवल 2 ददनो ों के दलए काया करता है. A दकतने

ददनो ों में दीवारा का शेष भाग पूरा करेगा?

(a) 13(1/3) days (b) 7(1/3) days (c) 6(1/3) days (d) 7 days

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Q12. A and B can finish a work in 10 days while B and C can do it in 18 days. A started the work, worked for 5 days, then B worked for 10 days and the remaining work was finished by C in 15 days. In how many days could C alone have finished the whole work?

A और B एक काया को 10 ददन में पूरा कर सकते हैं जबदक B और C इस काया को 18 ददन में पूरा

कर सकते हैं. A काया करना शुरू करता है और 5 ददन के दलए काया करता है, दिर B, 10 ददन के

दलए काया करता है दिर शेष काया C द्वारा 15 ददन में पूरा दकया गया. C अकेले काया दकतने ददन में

पूरा करेगा?


Q13. A certain number of men can do a work in 60 days. If there were 8 men more it could be finished in 10 days less. How many men are there?

परुषो ों की एक दनदित सोंख्या एक काया को 60 ददनो ों में कर सकती है. यदद उसमें 8 पुरुष अदिक

जुड़ जाएँ तो इसे 10 ददन कम में पूरा दकया जा सकता है. वहाों पर दकतने पुरुष हैं?

(a) 75 men (b) 40 men (c) 48 men (d) 45 men

Q14. A and B can do a job in 16 days and 12 days respectively. B has started the work alone 4 days before finishing the job, A joins B. How many days has B

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worked alone?

A और B एक काया को क्रमश: 16 ददन और 12 ददन में पूरा कर सकते हैं. B काया पूरा होने से 4

ददन पहले काया अकेले करना शुरू करता है, दिर A , B से जुड़ता है. B ने अकेले दकतने ददन काया

दकया?


Q15. Raju can do a piece of work in 10 days, Vicky in 12 days and Tinku in 15 days. They all start the work together, but Raju leaves after 2 days and Vicky leaves 3 days before the work is completed. In how many days is the work completed?

राजू एक काया को 10 ददन में पूरा कर सकता है, दवक्की उसे 12 ददन में और दटोंकू 15 ददन में पूरा

कर सकता है. वे सभी एकसाथ काया करना शुरू करते हैं, लेदकन 2 ददन बाद राजू काया छोड़ देता

है और दवक्की काया पूरा होने के 3 ददन पहले काया छोड़ देता है. काया दकतने ददनो ों में पूरा होगा?


CHEMISTRY

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Q1. Which among the following is white phosphorus?

निम्ननिखित में से कौि सा सफेद फास्फोरस है?

(a) P1

(b) P6

(c) P4

(d) P5

Show Answer

Ans.(c)

Sol. The most important form of elemental phosphorus from the perspective of applications and

chemical literature is white phosphorus. It consists of tetrahedral P4 molecules, in which each atom

is bound to the other three atoms by a single bond.

Q2. Alkali metals can –

अल्कािी िातुएं-

(a) Be highly stable at room temperature/ कमरे के तापमाि पर अत्यनिक खथिर रहती है

(b) Vaporize at room temperature/ कमरे के तापमाि पर वाष्पीकृत हो जाती है

(c) Easily gain electrons/ आसािी से इिेक्ट्र ॉि प्राप्त करती है

(d) Easily lose electrons/ आसािी से इिेक्ट्र ॉि िो देती है

Show Answer

Ans.(d)

Sol. Alkali metals have one electron in their outer shell so alkali metal can easily lose electrons.

Q3. What does a catalyst do in a reaction?

एक उते्प्ररक प्रनतनक्रया में क्या करता है

(a) Changes potential energy of reactants/ प्रनतनक्रयाओं की खथिनतज ऊजाय बदिता है

(b) Changes kinetic energy of reactants/ प्रनतनक्रयाओं की गनतशीि ऊजाय बदिता है

(c) Changes potential energy of products/ उत्पादो ंकी खथिनतज ऊजाय बदिता है



(d) Changes activation energy/ सनक्रयण ऊजाय बदिता है

Show Answer

Ans.(d)

Sol. Catalysis is the increase in the rate of a chemical reaction due to the participation of an

additional substance called a catalyst, which is not consumed in the catalyzed reaction and can

continue to act repeatedly. Thus, changes activation energy

Q4. Adding which substance gives green colour to glass?

कौि सा पदािय ग्लास को हरा रंग देता है?

(a) Calcium oxide/ कैखशशयम ऑक्साइि

(b) Iron oxide/ आयरि ऑक्साइि

(c) Chromium oxide/ क्रोनमयम ऑक्साइि

(d) Manganese oxide/ मैंगिीज ऑक्साइि

Show Answer

Ans.(c)

Sol. Chromium oxide is used to create green glass

Q5. Which among the following is present inside the nucleus of an atom?

निम्ननिखित में से कौि एक परमाणु के िानभक के अंदर मौजूद होता है?

(a) Protons and Neutrons /प्रोट्ॉि और नू्यट्र ॉि

(b) Electrons and Protons /इिेक्ट्र ॉि और प्रोट्ॉि

(c) Neutrons and Electrons /नू्यट्र ॉि और इिेक्ट्र ॉि

(d) Neutrons, Protons, Electrons /नू्यट्र ॉि, प्रोट्ॉि, इिेक्ट्र ॉि

Show Answer

Ans.(a)

Sol. There are two types of particle in the nucleus of an atom the proton and the neutron



Q6. What is baking soda?

बेनकंग सोिा क्या है?

(a) Aluminium bicarbonate /एलू्यनमनियम बाइकाबोिेट्

(b) Sodium isolate /सोनियम आईसोिेट्

(c) Sodium bicarbonate /सोनियम बाइकाबोिेट्

(d) Aluminium sulphate /एलू्यनमनियम सले्फट्

Show Answer

Ans.(c)

Sol. Baking soda is also known as Sodium bicarbonate. It is a chemical compound with the formula

NaHCO₃. It is a salt composed of sodium ions and bicarbonate ions. Sodium bicarbonate is a white

solid that is crystalline but often appears as a fine powder

Q7. Which among the following elements is a liquid at room temperature?

निम्ननिखित में से कौि-सा तत्व सामान्य तापमाि पर द्रव्य है?

(a) Phosphorus / फास्फोरस

(b) Mercury / मरकरी

(c) Sodium / सोनियम

(d) Aluminium / एलू्यनमनियम

Show Answer

Ans.(b)

Sol. There are two elements that are liquid in room temperature which are Bromine (Br) and

Mercury (Hg).

Q8. Which among the following is an endothermic reaction?

निम्ननिखित में से क्या ऊष्माशोषी प्रनतनक्रया है

(a) Respiration/ श्वसि

(b) Combustion/ ज्विि

(c) Sweating/ पसीिा आिा



(d) Burning of natural gas/ प्राकृनतक गैस का जििा

Show Answer

Ans.(c)

Sol. Endothermic process describes a process or reaction in which the system absorbs energy from

its surroundings. Sweating is a endothermic reaction

Q9. Name the catalyst used in the conversion of milk into curd.

दूि के दही में रूपांतरण में प्रयुक्त उते्प्ररक का िाम बताइये?

(a) Pepsin/ पेखिि

(b) Invertase/इन्वटे्स

(c) Lactase/िेके्ट्स

(d) Diastase/िाईटे्स

Show Answer

Ans.(c)

Sol. Milk is converted into curd or yogurt by the process of fermentation. Milk consists of globular

proteins called casein. The curd forms because of the chemical reaction between the lactic acid

bacteria and casein. Thus, lactase is the catalyst used in conversion of milk into curd

Q10. __________ fiber is used in making bristles for brushes.

ब्रश के नब्रसि बिािे में __________ फाइबर का उपयोग नकया जाता है

(a) Kevlar / केविर

(b) Nylon-66 / िायिॉि -66

(c) Terylene / टे्रीिीि

(d) Lexan /िेक्सि

Show Answer

Ans.(b)



Sol. Nylon 66 is a type of polyamide or Nylon. It is used in plastic Industries in making bristles for

brushes

Q11. Acids turn ______ litmus _______.

एनसि _______ निट्मस को _______ में पररवनतयत कर देता है.

(a) red, blue /िाि, िीिा

(b) green, yellow/हरा, पीिा

(c) blue, red /िीिा, िाि

(d) yellow, green/पीिा, हरा

Show Answer

Ans.(c)

Sol. Acid turns blue litmus paper red

Q12. Automobile exhaust leads to a poisonous pollutant

ऑट्ोमोबाइि निकास नकस जहरीिे प्रदूषक को बढ़ाता है?

(a) Carbon Dioxide/ काबयि िाइआक्साइि

(b) Sulphur Dioxide/ काबयि िाइक्साइि

(c) Carbon Monoxide/ काबयि मोिोऑक्साइि

(d) Nitrous Oxide/ िाइट्र स ऑक्साइि

Show Answer

Ans.(c)

Sol. Carbon Monoxide is a colorless, odorless, tasteless gas that's produced during incomplete

combustion of any fuel. It is a pollutant released by automobiles

Q13. What is the full form of PVC?

पीवीसी का पूरा रूप क्या है?



(a) Phosphonil vinyl Carbonate /फॉस्फोनमि नविीि काबोिेट्

(b) Polyvinyl S Carbonate पॉिीनविानयि एस काबोिेट्

(c) Polyvinyl Carbonate /पॉिीनविानयि काबोिेट्

(d) Polyvinyl Chloride /पॉिीनविानयि क्लोराइि

Show Answer

Ans.(d)

Sol. Full form of PVC is Polyvinyl chloride

Q14. Aromatic hydrocarbons contain at least _____ benzene like ring in their molecules?

सुगंनित हाइिर ोकाबयि में कम से कम _____ बेंजीि जैसे छले्ल उिके अणुओं में होते हैं.

(a) four /चार

(b) three /तीि

(c) two /दो

(d) one /एक

Show Answer

Ans.(d)

Sol. Aromatic hydrocarbons contain at least one benzene like ring in their molecules

Q15. Chromite is an ore/mineral of?

क्रोमाइट् ___का एक अयस्क / िनिज है.

(a) Zinc /नजंक

(b) Uranium /यूरेनियम

(c) Chromium /क्रोनमयम

(d) Titanium /ट्ाइटे्नियम

Show Answer

Ans.(c)



Sol. Chromite is the only ore of chromium, a metal essential for making stainless steel, nichrome,

chromeplating, pigments, refractories, chemicals and pharmaceuticals

CALENDER

1. If two days after day after tomorrow is Sunday, what day was the day before yesterday?

(1) Wednesday

(2) Tuesday

(3) Monday

(4) Sunday

2. A clock only with only dots marking 3, 6, 9 and 12 position has been kept upside down in front of

a mirror. A person reads the time in the reflection of the clock as 4.50. What is the actual time?

(1) 08 : 10

(2) 02 : 40

(3) 04 : 50

(4) 10 : 20

3. A clock only with dots marking 3, 6, 9 and 12 O’clock position has been kept upside down in front

of a mirror. A person reads the time in the reflection of the clock as 10 : 20. What is the actual time?

(1) 08 : 10

(2) 02 : 40

(3) 04 : 50

(4) 10 : 20

4. If day before yesterday was Tuesday, the day after tomorrow will be

(1) Monday

(2) Wednesday

(3) Friday

(4) Saturday



5. If three days after today will be Tuesday, what day was four days before yesterday?

(1) Tuesday

(2) Sunday

(3) Monday

(4) Wednesday

6. A clock goes slow from midnight by 5 mts. at the end of the first hour, by 10 mts. at the end of

the second hour, by 15 mts. at the end of the 3rd hour and so on. What will be the time by this clock

after 6 hours?

(1) 6 : 00 am

(2) 5 : 30 am

(3) 6 : 30 am

(4) 5 : 15 am

7. A clock goes fast by one minute during the first hour, by two minutes at the end of the second

hour, by 4 minutes at the end of 3rd hour, by eight minutes by the end of 4th hour, and so on. At the

end of which hour, will it be fast by just over sixty minutes?

(1) Fifth

(2) Sixth

(3) Seventh

(4) Eighth

8. If day before yesterday was Thursday, what day will be four days after tomorrow?

(1) Monday

(2) Thursday

(3) Sunday

(4) Wednesday

9. If Friday falls on 15th of September 2000, what will be the day of 15th of September 2001?



(1) Friday

(2) Saturday

(3) Thursday

(4) Sunday

10. If the day that will come two days after tomorrow is Thursday, what day of the week was three

days before yesterday?

(1) Monday

(2) Tuesday

(3) Wednesday

(4) Thursday

1.3

2.2

3.1

4.4

5.3

6.2

7.3

8.2

9.2

10.4

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