In a `p-n` junction photo cell, the value of the of the photo electromotive force produced by monochromatic light is proportional to

Options

A. the barrier voltage at the `p-n` junction
B. the intensity of the light falling on the cell
C. the frequency of the light falling on the cell
D. the voltage applied at the `p-n` junction

Answer

B

Explanation

When a light (wavelength sufficient to break the covalent bond) falls on the junction, new hole electron pairs are created. No. of produces electron hole pair depends upon no. of photons. So photo emf or current is proportional to intensity of light.