Question

According to wave theory of light, electrons from the metal surface knock out -

• A. instantly.
• B. with time lag.
• C. both instantly and with time lag, depends on the metal surface.
• D. both instantly and with time lag, depends on the radiation incident.

Answer 1

The correct option is B with time lag.

According to wave theory of light, light energy is uniformly distributed among the electrons.

The electron will take some time to accumulate enough energy to escape from the metal surface.

Therefore, there should be a time lag.

Hence, option $\left(B\right)$ is the correct answer.