Question 21
Question 21 of 40
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Older MCQs might not have the typical A, B, C, D choices. They have choices 1, 2, 3, and a combination of them is the answer. Below is the key that maps such combinations to the answer.
A 1, 2 and 3 are correct
B 1 and 2 only are correct
C 2 and 3 only are correct
D 1 only is correct
Topics Tested
3. Waves
3.3. Electromagnetic spectrum

Describe the harmful effects on people of excessive exposure to electromagnetic radiation, including: (a) microwaves; internal heating of body cells (b) infrared; skin burns (c) ultraviolet; damage to surface cells and eyes, leading to skin cancer and eye conditions (d) X-rays and gamma rays; mutation or damage to cells in the body

2. Thermal physics
2.3.3. Radiation

Describe experiments to distinguish between good and bad emitters of infrared radiation