Question

In the photoelectric effect, if the light below is NOT causing any electrons to be ejected from the metal, which of the following changes will cause the light to begin to eject electrons?

A) Increasing the intensity of the light
B) Decreasing the frequency of the light
C) Increasing the wavelength of the light
D) Increasing the amplitude of the light

Answer 1

In the photoelectric effect, the frequency of light is the determining factor for electron ejection. Decreasing the frequency of the light will prevent electron ejection. The correct answer is B) Decreasing the frequency of the light,

Step-by-step explanation:

In the photoelectric effect, the frequency of light is the determining factor for whether or not electrons will be ejected from the metal surface, not the intensity, wavelength, or amplitude.

In order for light to eject electrons, it must have a frequency equal to or greater than the threshold frequency of the metal. The threshold frequency is the minimum frequency required to eject electrons.

So, the correct answer is B) Decreasing the frequency of the light, because a decrease in frequency would bring the light below the threshold frequency and prevent electron ejection.