When ultraviolet rays incident on metal plate then photoelectric effect does not occur, it occurs by incidence of :-

Question

When ultraviolet rays incident on metal plate then photoelectric effect does not occur, it occurs by incidence of :- (A) infrared rays (B) X-rays (C) radio wave (D) micro wave.

Tardigrade Admin · Accepted Answer

Alkali metals, viz, lithium, sodium, potassium shows photoelectric effect even with visible light. Photo-electric emission depends on the work function

(W)

of the metal surface. If the frequency

v

of the incident ray is less than certain frequency

v_{0}

known as threshold frequency, no photoelectric effect is possible.

W = h v_{0}

, is different for different materials.
Therefore, when ultra-violet rays fail to emit photoelectrons, rays like X-rays with higher frequency should be used.

Q. When ultraviolet rays incident on metal plate then photoelectric effect does not occur, it occurs by incidence of :-

infrared rays

X-rays

radio wave

micro wave.