The frequency of a light wave in air is 5.3 * 10¹⁴ Hz. Is the fre-quency of this wave higher, lower, or the same after the light enters a piece of glass?

Answer:same

Explanation:

Frequency will remain same irrespective of refractive index of material because frequency is the ratio of velocity and wavelength.

When a wave travel from one material to another then its wavelength and velocity changes in that medium and they adjust itself to give same frequency