Assertion : Photosensitivity of a metal is high if its work funct… - Vidyadip

MCQ

Assertion : Photosensitivity of a metal is high if its work function is small.
Reason : Work function $= hf_0$ where $f_0$ is the threshold frequency.

A
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
✓
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
C
If the Assertion is correct but Reason is incorrect.
D
If both the Assertion and Reason are incorrect.

✓

Answer

Correct option: B.

If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

b
The photosensitivity of a metal is high when its work function is small. Work function of a metal depends not on the threshold frequency but on the nature of the metal.

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