Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Waves
356 practice questions
Topics covered
Practice questions
251–260 of 356
Question 251
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 252
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 253
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 254
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 255
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 256
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 257
1 mark · Easy
Answer and see the solution →State one way that infrared radiation can be harmful to the human body.
Question 258
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 259
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.
Question 260
1 mark · Easy
Answer and check →Which is a correct use of infrared radiation?
- A.Heating food in a grill
- B.Detecting gamma rays
- C.Transmitting X-rays for dental pictures
- D.Emitting blue light from an LED