KS3 Physics revision questions 3 - Energy Resources, Energy Transfers, Light, Sound

Level 6 Questions

17. Light shines onto a ball. Naomi is looking at the ball.

(a) Describe how light from the lamp lights up the ball and makes it visible to Naomi.

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2 marks

(b) (i) Naomi uses different colours of light and different coloured balls.

Complete the table to show the colours that the balls appear to Naomi.

2 marks

(ii) Why does a black object appear black in any light?

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1 mark

(c) Choose from the following terms to complete the sentences below.

less than equal to greater than

At a plane mirror, the angle of incidence is …………………………..…

the angle of reflection. The distance from the object to the mirror is

…………………..…. the apparent distance from the mirror to the image.

2 marks

(d) A beam of white light shines onto a sheet of white paper. An identical beam of lightshines onto a mirror. The light is scattered from the paper and reflected from themirror.

Describe how scattering by paper and reflection by a mirror are different from eachother.

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2 marks

Maximum 9 marks

18. A ray of blue light falls on a glass prism as shown in the diagram.

(a) On the diagram, draw the path of the blue ray through the prism and from the prism to the screen. Use a ruler.

2 marks

(b) The blue ray is replaced by a ray of white light.

(i) What would you now see on the screen?

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1 mark

A red filter is placed between the prism and the screen.

(ii) What would you now see on the screen?

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1 mark

(iii) Explain how the red filter causes the change.

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1 mark

Maximum 5 marks

19. The diagram below shows the shapes and positions of five glass objects.

Harriet put a square of black card on top of each glass object.
She shone a ray of red light onto each object.

The diagrams below show the rays of light going under the cards and coming out again.
Which object is under each card? Write the correct letter below each diagram.
One has been done for you.

4 marks

Maximum 4 marks

20. (a) (i) Air contains nitrogen.
In the box below draw five circles, , to show the arrangement of particles in nitrogen gas.

1 mark

(ii) Zeena carries a personal emergency alarm.
It uses nitrogen gas to produce a very loud sound.

The nitrogen gas in the container is under much higher pressure than the nitrogen gas in the air.

How does the arrangement of nitrogen particles change when the gas is under higher pressure?

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1 mark

(b) Use words from the boxes below to complete the sentence.

The rate at which the nitrogen particles hit the inside of the container is ...... the rate at which nitrogen particles hit the outside of the container.

1 mark

(c) Zeena pushes the lid down and nitrogen gas escapes through the diaphragm.
The diaphragm vibrates and produces a sound.

The pattern on the oscilloscope screen below represents the soundwave produced by the alarm.

(i) The loudness of the sound produced by the alarm decreases between X and Y.

How can you tell this from the graph?

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1 mark

(ii) The pitch of the sound produced by the alarm stays the same between X and Y.

How can you tell this from the graph?

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1 mark

maximum 5 marks

21. The diagram shows a ray of light hitting the surface of a mirror made from thick glass.
The incident ray is both reflected and refracted.

(a) (i) Give the letters of the two reflected rays.

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1 mark

(ii) Give the letter of one refracted ray.

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1 mark

(b) The incident ray is brighter than ray A.
Give one reason for this.

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1 mark

maximum 3 marks

22. Fossil fuels are used to generate electricity, but over half of the world’s population uses biomass as a fuel.

(a) What is ‘biomass’, which is used as a fuel?

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1 mark

(b) Biomass and fossil fuels are both energy resources. What is the original source ofthisenergy?

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1 mark

(c) Give the names of three fossil fuels which are often burned to generate electricity.

1......

2......

3......

1 mark

(d) Fossil fuels are often described as non-renewable energy resources.
Explain why they are called ‘non-renewable’.

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1 mark

(e) There are advantages and disadvantages of burning different fuels.

(i) Give one advantage of using biomass rather than fossil fuel as an energyresource.

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1 mark

(ii) Give one advantage of using fossil fuel rather than biomass as an energyresource.

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1 mark

(iii) Give one disadvantage of using both fossil fuel and biomass.

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1 mark

Maximum 7 marks

23. (a) Jacquie has a mobile phone. Energy is stored in the battery of the phone.
The drawing shows the battery being charged.

(i) Which energy transfer takes place in the battery as it is being charged? Tick the correct box.

chemical to sound sound to thermal

electrical to chemical thermal to electrical

1 mark

(ii) When the battery is fully charged, Jacquie unplugs the phone.

Which energy transfers take place when the mobile phone rings?
Tick the correct box.

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chemical to electrical to sound
electrical to chemical to sound
kinetic to electrical to sound
thermal to electrical to sound

1 mark

(b) Jacquie can change the ring-tone of her phone.
The diagrams below show the patterns made by four sound waves on an oscilloscope screen.
They are all drawn to the same scale.

Write the letter of the sound wave that matches each of the descriptions below.

(i) a loud sound with a low pitch ......

(ii) a quiet sound with a high pitch ......

(iii) a loud sound with a high pitch ......

3 marks

Maximum 5 marks

24. The photograph shows some pupils in a log car on a theme-park ride.

The drawing below shows the ride.
The letters A, B, C, D, E and F show different points along the track.

The car starts from A and travels to F, where it stops by hitting a bumper.
At E the car enters a trench filled with water.

(a) (i) At which two points does the car have no kinetic energy?
Give the two correct letters.

...... and ......

1 mark

(ii) At which point does the car have the most gravitational potential energy?
Give the correct letter.

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1 mark

(iii) At which point does the car have some kinetic energy and the least gravitational potential energy?
Give the correct letter.

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1 mark

(b) (i) The cars are not powered by a motor.
What force causes the cars to move along the track from B to C?

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1 mark

(ii) When a car splashes through the water at E, it slows down.
What force acts on the car to slow it down?

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1 mark

(c) Complete the sentence below by choosing from the following words.

When the car hits the bumper at F, its ...... energy

is transferred into ...... energy and

...... energy.

3 marks

maximum 8 marks

25. The drawing below shows a garden water feature. It is solar-powered.

The solar cell absorbs energy from the Sun.
The solar cell is connected to a motor in the bowl.
The motor drives a pump.
Water is pumped up to the jug and it flows back down to the bowl.

(a) Use the information above to help you to complete the following sentences.
Choose words from the list.

(i) The useful energy change in the solar cell is from
light to ...... energy.

1 mark

(ii) The useful energy change in the motor is from
electrical energy to ...... energy.

1 mark

(iii) As the water flows from the jug to the bowl ...... energy is changed into ...... energy.

2 marks

(b) Give one advantage and one disadvantage of using a solar cell to power the water feature.

advantage ......

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1 mark

disadvantage ......

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1 mark

maximum 6 marks

26. The drawings below show Caroline diving into a swimming pool.
As she falls, gravitational potential energy is changed into kinetic energy.

(a) Why does Caroline have no kinetic energy at A?

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1 mark

(b) The table shows Caroline’s gravitational potential energy and kinetic energy at four stages of the dive.

stage of the dive / total energy
(kJ) / gravitational potential energy (kJ) / Kinetic energy (kJ)
A / 8 / 8 / 0
B / 8 / 7 / 1
C / 8 / 4 / 4
D / 8 / 0

(i) Write the missing kinetic energy value for stage D in the table.

(II) As Caroline falls there is no loss of energy to the air.
How do the energy values for stages A, B, C and D show this?

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2 marks

(c) (I) Give the name of the force that causes Caroline to speed up as she falls.

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(ii) Caroline takes 0.5 s to fall from A to B and from B to C and from C to D.

How can you tell from the drawings that she is speeding up as she falls?

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2 marks

(d) When Caroline enters the water she slows down.
Give the name of the force that slows her down.

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1 mark

maximum 6 marks

27. (a) A torch battery is an energy resource. How is the energy stored in a torch battery?
Tick the correct box.

as chemical energy

as kinetic energy

as potential energy

as thermal energy

1 mark

(b) When a torch is switched on, energy is transferred from the battery to the bulb.
How is energy transferred from the battery to the bulb?
Tick the correct box.

by electricity

by light

by sound

by thermal energy

1 mark

(c) Energy is transferred from the torch bulb to the surroundings.

Choose from the following terms to complete the sentences.

electricity light sound thermal transfer

(i) Energy is transferred from the torch bulb to the surroundings in a

useful way by ......

1 mark

(ii) Some energy is wasted. The wasted energy is transferred from the

bulb to the surroundings by ......

1 mark

(d) The torch is lifted up and put on a high shelf.

Energy is transferred to the torch as it is lifted up. The energy is stored in the torch while it stays on the shelf.
What energy has the torch gained?

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1 mark

Maximum 5 marks

28. A teacher set up the following apparatus behind a safety screen.
She placed 1 g of icing sugar in the end of the rubber tubing inside the tin, as shown below.

The teacher blew through the other end of the rubber tubing.
The icing sugar came into contact with the flame.
There was a loud explosion and the lid was blown off the tin.

(a) Complete the following sentence describing the energy changes which took place.

...... energy in the icing sugar changed to

...... energy and ...... energy.

3 marks

(b) As a result of the explosion, the lid of the tin was pushed off.
Explain what had happened to the gas molecules inside the tin to make this happen.

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2 marks

(c) When icing sugar is burned in this experiment, the gas used and the gas produced are the same as when energy is released from sugar in the cells of the body.

(i) Which gas, in the air, is used when the icing sugar burns?

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1 mark

(ii) Give the name of the gas produced when the icing sugar burns.

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1 mark

(d) The table below shows the energy values of four food substances.

food substance / energy value, in
kJ per 100 g
icing sugar / 1680
curry powder / 979
flour / 1450
custard powder / 630

The teacher repeated the experiment with 1 g of custard powder.
What difference would this make to the experiment?

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1 mark

Maximum 8 marks

29. The drawings show a weightlifter. The stages in weightlifting are labelled A, B, C, D and E.

(a) (i) Complete the sentences below.

As the weights were lifted up, energy was transferred from

the man to the weights. This energy had been stored as

……………………… energy in the ………………………… of

the man’s arms.

2 marks

(ii) How was energy stored in the weights at stage C?

Tick the correct box.

as chemical energy / / as elastic energy /
as kinetic energy / / as gravitational potential
energy /

1 mark

(b) Complete the sentences below.

(i) In stage D, as the weights were falling, the energy was transferred

from …………………………… energy to…………………………… energy.

1 mark

(ii) In stage E, as the weights hit the floor, the energy was transferred

from …………………………… energy to …………………………… energy.

1 mark

Maximum 5 marks

30. The tides can be used to generate electricity. A dam is built across a river estuary, as shownbelow.

(a) The water is higher on one side of the dam than on the other. As the water begins to flow through the dam it turns a turbine. The turbine generates electricity.
Describe the useful energy changes which take place in this process.