Below are four statements about electromagnetic radiation.
1 Microwaves have a shorter wavelength than all other electromagnetic waves.
2 For identical amplitudes, waves with the largest wavelength transfer the most
energy.
3 The speed of electromagnetic waves is inversely proportional to their frequency.
4 Ultraviolet radiation can cause cataracts.
Which of these statements is / are correct?
Answer:
Statement 1 is incorrect; microwaves have a longer wavelength than infrared radiation and many
other parts of the electromagnetic spectrum.
Statement 2 is incorrect; energy increases with frequency (and consequently decreases with
wavelength), and so in fact the shortest wavelengths transfer the most energy.
Statement 3 is incorrect; the wavelength is inversely proportional to frequency, and the speed is the
constant for this relationship (š£ = š Ć š).
Statement 4 is correct; ultraviolet waves are higher frequency than visible light, so carry more energy
and can damage corneas, causing cataracts.
The answer is D