Question

A beam of monochromatic radiation is incident on a photosensitive surface.

Answer the following questions giving reasons :

(i) Do the emitted photoelectrons have the same kinetic energy?

(ii) Does the kinetic energy of the emitted electrons depend on the intensity of incident radiation?

(iii) On what factors does the number of emitted photoelectrons depend?

Answer 1

(i) Yes, all emitted photoelectrons have same kinetic energy as the kinetic energy of emitted photoelectrons depending upon frequency of the incident radiation for a given photosensitive surface.

(ii) No, the kinetic energy of emitted electrons does not depend on the intensity of incident radiation. If the intensity is increased, number of photons will also increase but energy of each photon remains same as the frequency is also same, The maximum kinetic energy depends on frequency not on intensity.

(iii) The number of emitted photoelectrons depends only on intensity of incident light.