Question

What is the effect of intensity on the stopping potential?

(a) As intensity increases, stopping potential increases linearly

(b) As intensity increases, stopping potential decreases linearly

(c) As intensity decreases, stopping potential increases exponentially

(d) No effect

The question was asked in an interview for job.

This is a very interesting question from PhotoElectric Effect topic in division Quantum Physics of Engineering Physics I

Answer 1

Right choice is (d) No effect

The explanation: Changing the intensity of incident radiation does not affect the stopping potential. As the intensity increases, the number of photoelectrons ejected increases. However, the maximum velocity attained by them remains independent of the intensity of the radiation. It only depends on the frequency of the incident radiation.