IJ Physics Summer Revision of Class 1 content –revision list- practise questions – mark schemes
(NB the following may be assessed in the IGSCE in any context: understanding of experimental technique, identification and understanding of the independent, dependent and control variables, ability to take averages and talk about errors (human mistake, a zeroing error on scales, parallax from not reading a dial at eye level etc), units, unit conversions
Topic list: Hooke’s law
describe experiments to investigate how extension varies with applied force for helical springs, metal wires and rubber bands
understand that the initial linear region of a force-extension graph is associated with Hooke’s law
describe elastic behaviour as the ability of a material to recover its original shape after the forces causing deformation have been removed
Topic list: Density and Pressure
use the following units: kilogram (kg), kilogram/metre3 (kg/m3), metre (m), metre2 (m2 ), metre3 (m3), newton (N), pascal (Pa)
know and use the relationship between density, mass and volume: density = mass / volume ρ = m / V
describe experiments to determine density using direct measurements of mass and volume
know and use the relationship between pressure, force and area: pressure = force / area p = F / A
understand that the pressure at a point in a gas or liquid which is at rest acts equally in all directions
know and use the relationship for pressure difference: pressure difference = height × density × g p = h × ρ × g
Topic list: energy
use the following unit: joule (J)
describe energy transfers involving the following forms of energy:
thermal (heat), light, electrical, sound, kinetic, chemical, nuclear and potential (elastic and gravitational)
understand that energy is conserved
know and use the relationship: efficiency = useful energy output / total energy input
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describe a variety of everyday and scientific devices and situations,
explaining the fate of the input energy in terms of the above relationship, including their representation by Sankey diagrams
describe how energy transfer may take place by conduction, convection and radiation
explain the role of convection in everyday phenomena
explain how insulation is used to reduce energy transfers from buildings and the human body
Topic list: electromagnetic spectrum
To understand that light is part of a continuous electromagnetic
spectrum which includes radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray radiations
To know that electromagnetic waves travel at the same speed in free space, 3 x 108 m/s
To identify the order of the electromagnetic spectrum in terms of
decreasing wavelength and increasing frequency, including the colours of the visible spectrum
To explain some of the uses of electromagnetic radiations, including:
radio waves: broadcasting and communications microwaves: cooking and satellite transmissions infrared: heaters and night vision equipment visible light: optical fibres and photography ultraviolet: fluorescent lamps x-rays: observing the internal structure of objects and materials
and medical applications gamma rays: sterilising food and medical equipment
To understand the detrimental effects of excessive exposure of the human body to electromagnetic waves, including:
microwaves: internal heating of body tissue infrared: skin burns ultraviolet: damage to surface cells and blindness gamma rays: cancer, mutation and describe simple protective measures against the risks
Topic list: astronomy and orbits
To understand gravitational field strength, g, and recall that it is different on other planets and the moon from that on the Earth
To explain that gravitational force: causes moons to orbit planets causes the planets to orbit the sun causes artificial satellites to orbit the Earth
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causes comets to orbit the sun To be able to identify gravity acting between two objects on a
force diagram. describe the differences in the orbits of comets, moons and
planets
use the relationship between orbital speed, orbital radius and
time period: orbital speed = 2 x π x orbital radius / time period v = 2 x π x r / T
To understand “the address of the universe” that is: the universe is a large collection of billions of galaxies a galaxy is a large collection of billions of stars our solar system is in the Milky Way galaxy
To be able to describe a geostationary and a polar satellite and their uses.
Topic list: electricity revision checklist (C1 only)
To understand and identify the hazards of electricity including frayed cables: o long cables, o damaged plugs, o water around sockets, o pushing metal objects into sockets
To understand the uses of insulation, double insulation.
To understand why appliances are earthed, and what would happens if electrical appliances were not earthed.
To understand how a fuse and circuit breakers works in a range of domestic appliances.
To describe the concept of electrical resistance, and the effect of changing resistance on the current in a circuit.
To understand that a current in a resistor results in the electrical transfer of energy and an increase in temperature, and how this can be used in a variety of domestic contexts.
Energy resources and electricity generation
describe the energy transfers involved in generating electricity using: wind water geothermal resources solar heating systems solar cells fossil fuels nuclear power
describe the advantages and disadvantages of methods of large-scaleelectricity production from various renewable and non-
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renewableresources
Hooke’s law
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Density
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Density and the experimental method
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Pressure
Q1.
A student wants to calculate the pressure he exerts on the floor when he stands on one foot.
He records these measurements.
(a) (i) Complete the table by adding the unit for weight.
(1)(ii) Which piece of equipment should the student use to measure his weight?
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(b) Suggest how the student measured the area of the floor in contact with his foot.
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(c) (i) State the equation linking pressure, force and area.
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(ii) Calculate the pressure that the student's foot exerts on the floor.(2)
pressure = ........................................................... N/cm2
(Total for question = 8 marks)
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Energy transfers
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Energy transfers and energy efficiency & fuses
1. This question is about an electric kettle.
(a) The Sankey diagram represents the energy transfers taking place when the kettleheats some water.
What is the efficiency of the kettle?(1)
A 0.1
B 0.9
C 200
D 1800
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(b) Why does the heating element in the kettle get hot when its electrical supply isswitched on?
(2)
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(c) The power of the heating element in the kettle is 2000 W when it is connected to a230 V mains supply.
(i) State the equation linking power, current and voltage.(1)
(ii) Show that the current in the heating element is approximately 9 A.(2)
Current = ........................................................... A
(iii) The plug of the kettle has a fuse.Fuses are available in values of
1 A 3 A 7 A 13 A
Identify the fuse that is the most suitable for this kettle, and explain why.(2)
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(Total for question = 8 marks)
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Energy loss experiments
Q1. A student uses four containers, A, B, C and D, to investigate heat transfer.
The student places boiling water into each of the four containers.She then records how the temperature of the water in each container varies with time.(a) How could the student make sure that the investigation is a fair test?
(2)....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(b) (i) Explain which container loses the most thermal energy by radiation.
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(ii) Explain which container loses the most thermal energy by convection.(2)
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.........................................................................................................................................(c) After 20 minutes, container D has the highest temperature.
Explain why container D remains hot for the longest time.Refer to three methods of thermal energy transfer in your answer.
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(Total for question = 10 marks)
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The Electromagnetic spectrum
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Orbits
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Astronomy and orbits & the electromagnetic spectrum
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Electrical safety
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Methods of power generation (was missing from the revision list)
Q5.Some energy sources are renewable and other energy sources are non-renewable.
(a) (i) Explain what is meant by the term non-renewable.(1)
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(ii) Give an example of a non-renewable energy source.(1)
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(b) The photograph shows a wind farm that generates electricity for the National Grid.
(i) Some people think that wind farms are a good idea.Others disagree.Discuss the advantages and disadvantages of building more wind farms.
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(Total for question = 11 marks)
Q7.
The table gives information about some ways to generate electrical power.
An electricity supply company has enough power stations to cover the normal demand for electricity but not enough for cold conditions.
On cold days the demand for electrical power can suddenly increase by 20 000 MW.
The company needs to build new power stations to meet this increased demand.
Using only information in the table, evaluate which types of power station would be the most suitable to meet this increased demand.
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(Total for question = 5 marks)
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Mark Schemes
Hooke’s Law
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Density
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Density and the experimental method
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Pressure
Q1.
Energy transfers
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Energy transfers and energy efficiency & fuses
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Energy transfer experiments
The electromagnetic spectrum
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Orbits
Astronomy and orbits & The Electromagnetic spectrum
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Electrical safety
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Methods of power generation (was missing from the revision list)
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Not done yet, b (ii) in the answers is b(i) on the question sheet
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Q7.
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