Question

A photon of energy hu is absorbed by a free electron of a metal having work function w<hv. Then
(A) The electron is sure to come out
(B) The electron is sure to come out with a kinetic energy (hv - W)
C) Either the electron does not come out or it comes with a kinetic energy (hv-W)
D) it may come out with a kinetic energy less than (hv - W)​

Answer 1

answer : option (B) The electron is sure to come out with a kinetic energy (hv - W).

explanation : according to photoelectric theory, if a beam of light of a specific frequency is struck in the metal surface, electron ejects from the surface and ejected electrons have some kinetic energy.

means, if energy of incident photon , E = hv and threshold energy = w, where hv > w then, kinetic energy of emitted photon = hv - w.

so, option (B) is correct , The electron is sure to come out with a kinetic ene6 (hv - w).

Answer 2

Answer:D

Explanation:

Photoelectric effect is a random phenomena. So,

electron may come out with a kinetic energy less

than or equal to (hu – w) as some energy is lost

while escaping out.