Question

Assertion (A): Photoelectric current depends upon the intensity of the incident radiation.

Reason (R): Stopping potential is independent of the intensity of the incident radiation.

Options

• Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).

• Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).

• Assertion (A) is true, but Reason (R) is false.

• Both Assertion (A) and Reason (R) are false.

Answer 1

Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).

Explanation:

Photoelectric current depends on the intensity of the incident radiation because a higher intensity means more photons strike the metal surface per second, ejecting more photoelectrons. Hence, Assertion (A) is true.

The stopping potential is given by

eV₀ = K_max = hν − ϕ

It depends only on the frequency of the incident radiation and the metal’s work function and is independent of the intensity. Hence, Reason (R) is true.

However, the reason does not explain why the photoelectric current depends on intensity.

Hence, both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).