Question

In the case of refraction of light :
a) Frequency changes
b) Speed changes
c) Wavelength changes

• A. b and c are correct
• B. a is correct
• C. a, b, c are correct
• D. a and b are correct

Answer 1

Answer: (A)

Only speed and wavelength will change.
Frequency will not change because at the boundary/interface of the medium, the number of waves you send is the number of waves you receive, at the other side, almost instantly. Frequency doesn't change because it depends on travelling of waves across the interface.

But speed and wavelength change as the material on the other side may be different, so now it might have a longer/shorter size of wave and so the number of waves per unit time changes.