Question

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

• A. The voltage applied at the PN junction
• B. The barrier voltage at the PN junction
• C. The intensity of the light falling on the cell
• D. The frequency of the light falling on the cell

Answer 1

Answer: (C)

The intensity of the light falling on the cell

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