Question

In an experiment on photoelectric emission, the intensity of incident radiation is halved keeping its frequency constant. As a result ______.

Options

• cut-off potential will increase.

• maximum kinetic energy of photoelectrons will remain the same.

• photocurrent will increase.

• cut-off potential will decrease.

Answer 1

In an experiment on photoelectric emission, the intensity of incident radiation is halved keeping its frequency constant. As a result maximum kinetic energy of photoelectrons will remain the same.

Explanation:

According to Einstein’s photoelectric equation, K_max = hν − Φ. The maximum kinetic energy (K_max) and the cut-off potential (V₀, where eV₀ = K_max) are solely determined by the frequency of the incident radiation and the characteristics of the material. In frequency dependence, frequency is constant, K_max and V₀ remain unchanged. In Intensity dependence, intensity refers to the quantity of photons impinging upon a unit area within a unit of time. Photocurrent is directly proportional to intensity. If the intensity is reduced by fifty percent, the photocurrent will also decrease by fifty percent (not increase).