Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter
The Electromagnetic Spectrum
70 practice questions
Topics covered
Practice questions
21–30 of 33 · Easy
Question 21
1 mark · Easy
Answer and check →Which of the following is a common use of microwaves?
- A.Heating food in microwave ovens
- B.Medical X-rays for imaging bones
- C.Detecting heat loss with infrared cameras
- D.Controlling TVs with a remote control
Question 22
3 marks · Easy
Answer and see the solution →Microwaves are widely used in satellite communication and cooking.
(a)[1 mark]State one reason why microwaves are suitable for use in satellite communications.
(b)[2 marks]Explain why metal screens are used in the doors of microwave ovens.
Question 23
2 marks · Easy
Answer and see the solution →Explain one possible detrimental effect of excessive exposure to microwaves on the human body. Suggest one way to reduce the risk.
Question 24
1 mark · Easy
Answer and see the solution →State the relationship between an object's temperature and the amount of infrared radiation it emits.
Question 25
2 marks · Easy
Answer and see the solution →A person stands near an electric fire. Explain how the electric fire warms the person using infrared radiation.
Question 26
1 mark · Easy
Answer and check →Which statement about infrared radiation is correct?
- A.Infrared radiation can travel through a vacuum.
- B.Infrared radiation cannot travel through air.
- C.Infrared radiation is only present in sunlight.
- D.Infrared radiation is visible to the human eye.
Question 27
3 marks · Easy
Answer and see the solution →A loaf of bread is placed under a toaster grill. The grill heats up and glows red.
(a)[1 mark]Identify the type of electromagnetic radiation emitted by the hot grill.
(b)[2 marks]Explain how this radiation cooks the bread.
Question 28
1 mark · Easy
Answer and see the solution →State one way that infrared radiation can be harmful to the human body.
Question 29
2 marks · Easy
Answer and see the solution →Two identical beakers of water are placed at the same distance from an infrared lamp. Beaker 1 is covered with shiny foil, and Beaker 2 is covered with matte black paper. Both are left under the lamp for 5 minutes. Predict which beaker will be warmer at the end and explain why.
Question 30
2 marks · Easy
Answer and see the solution →A person checks their home for heat loss using an infrared camera. Explain why the camera is able to identify areas losing heat.