Question

Light of frequency 1.5 times the threshold frequency is incident on a photosensitive material. If the frequency of the incident light is halved and the intensity is doubled, photoelectric current becomes :

• A. Quadrupled
• B. Doubled
• C. Halved
• D. Zero

Answer 1

The correct option is D Zero

Frequency of light is 1.5 times of threshold frequency. Now frequency is made half.

So, new frequency will be $\frac{1.5f_T}{2}=0.75f_T$

So, this frequency is less than threshold frequency So, these will not be ejection of electrons from the metal surface. So, there will not be any current.
So, the answer is option (D).