Practice Paper 1 (Edexcel IGCSE Physics)

Which of the following statements provides evidence that the universe is expanding?

An astronomer observes that light from a galaxy has been shifted towards the blue end of the spectrum.

What can be deduced about the motion of the galaxy from this observation?

The diagram shows some wavelengths that were observed using light from a source in a laboratory:

The same wavelengths of light observed from a distant galaxy were found to be redshifted.

Which of the following statements about the redshifted light is correct?

The planet Mercury orbits the Sun.

Mercury takes 88 days to orbit the Sun.

The average radius of the orbit is 58 million km.

Calculate the average orbital speed of Mercury. Give the unit.

Comets also orbit the Sun.

(i) Name the force that causes comets and planets to orbit the Sun.

(ii) Add to the diagram in part (a) to show the orbit of a typical comet.

The speed of a comet changes during its orbit.

(i) On the orbit you have drawn, label with the letter X the position where the comet travels at its fastest speed.

(ii) Explain why the comet travels fastest at point X.

What is the absolute magnitude of a star a measure of?

The table gives some statements about the absolute magnitude scale.

Add ticks (✔) to the table to show which three statements are correct.

The number of turns on the primary coil of a step-down transformer is:

The photograph shows a simple d.c. electric motor.

When the switch is closed the coil spins. Explain why this happens.

(i) Describe two ways to increase the speed of rotation of the coil in this motor.

(ii) Suggest how to make the coil spin in the opposite direction.

The diagram shows the main parts of a nuclear reactor.

Draw a line linking each part of the reactor with its main function.

The first one has been done for you.

In a fission reaction, energy is transferred from the nuclear store of the particles to which store?

Explain the role of the moderator in a fission reaction.

Explain, in terms of neutrons, what is meant by controlled nuclear fission.

A teacher uses this apparatus to demonstrate radioactivity to his students.

The teacher needs to take some safety precautions.

Put one tick (✓) on each row to show whether the safety precaution is needed or not. Two have been done for you.

The teacher uses this method to investigate radioactivity.

• Place the detector 10 cm from the radioactive source
• Record the count with different absorbent materials between the source and the detector
• Repeat the investigation using a different radioactive source
• Also repeat the investigation without a source

The table shows his results.

(i) State why the teacher keeps the distance constant between the source and the detector.

(ii) Explain why there is a reading when no source is used.

(i) Explain which of the materials the teacher used is the best absorber of radiation.

(ii) A student makes this conclusion.

'Stone is the worst absorber of radiation.'

Evaluate this conclusion

A scientist placed a radioactive source in front of a Geiger-Muller detector and measured the count rate every 20 minutes.

The table shows her data.

The scientist corrects the count rate readings to allow for background radiation.

(i) State two sources of background radiation.

(ii) Describe how the scientist should measure the background radiation and correct the count rate readings.

(i) Plot a graph of the corrected count rate against time and draw the curve of best fit.

(ii) Use your graph to find the half-life of the radioactive source.

half-life = ...................................................... minutes

The scientist needs to reduce the risks when working with radioactive sources.

(i) Explain why radioactive sources can be dangerous.

(ii) Describe how the risks of working with radioactive sources can be reduced.

All gases above absolute zero exert a pressure on the walls of their container.

State the value of absolute zero in °C.

All gases above absolute zero exert a pressure on the walls of their container.

Explain, in terms of its molecules, how a gas exerts a pressure on the walls of its container.