Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Waves
356 practice questions
Topics covered
Practice questions
121–130 of 181 · Normal
Question 121
4 marks · Normal
Answer and see the solution →Microwaves are used in mobile phones to carry signals.
(a)[2 marks]Describe one benefit and one risk of using microwaves in mobile phone technology.
(b)[1 mark]Suggest one way people can reduce the risk you described in part (a).
(c)[1 mark]Explain why mobile phone microwaves do not cook your brain.
Question 122
3 marks · Normal
Answer and see the solution →A company is designing a new microwave oven. They want to ensure it is both efficient and safe.
(a)[2 marks]Explain how microwaves heat food inside an oven.
(b)[1 mark]Describe one design feature that makes a microwave oven safe for users.
Question 123
4 marks · Normal
Answer and see the solution →Microwaves are part of the electromagnetic spectrum and have a wide range of applications.
(a)[2 marks]Explain why microwaves are used to send signals to and from satellites, rather than radio waves.
(b)[2 marks]Describe one reason why microwave ovens cook food differently compared to conventional ovens.
Question 124
1 mark · Normal
Answer and see the solution →Which of the following is a detrimental effect of excessive exposure to microwaves in the home?
- A.Can cause burns to human tissue
- B.Causes electric shocks
- C.Can permanently magnetise metals
- D.Can damage bone structure
Question 125
3 marks · Normal
Answer and see the solution →A student is comparing different ways microwaves and radio waves are used in technology. Complete the table below by stating one key use for each wave, and one safety concern linked to each.
Wave Example of a use One safety concern Microwaves Radio waves Question 126
3 marks · Normal
Answer and see the solution →A person spends a long time standing close to a malfunctioning microwave oven that is leaking microwaves.
(a)[2 marks]State and explain one harmful effect this exposure could have on the person’s body.
(b)[1 mark]Suggest one way the design of a microwave oven helps to prevent this effect.
Question 127
2 marks · Normal
Answer and see the solution →A student claims that using mobile phones is completely safe since microwaves have less energy than other waves in the electromagnetic spectrum. Do you agree? Give one scientific reason for your answer.
Question 128
4 marks · Normal
Answer and see the solution →All objects emit infrared radiation. A hot stone is left to cool in a cold room.
(a)[2 marks]Explain why the stone emits more infrared radiation as its temperature increases.
(b)[2 marks]Name two household appliances or devices that use infrared radiation for their operation.
Question 129
2 marks · Normal
Answer and see the solution →State two uses of infrared radiation other than for heating.
Question 130
3 marks · Normal
Answer and see the solution →Special cameras designed to detect infrared waves can be used to find people in darkness, such as in a rescue operation after a building collapse. Infrared images show hot bodies as white shapes against a dark background.
(a)[3 marks]Explain why infrared cameras are useful for finding people in such situations.