MCQ
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Emission of electrons in photoelectric effect can be suppressed by applying a sufficiently negative electron potential to the photoemissive substance.
Reason (R): A negative electric potential, which stops the emission of electrons from the surface of a photoemissive substance, varies linearly with frequency of incident radiation.
In the light of the above statements, choose the most appropriate answer from the options given below:
  • A
    (A) is false but (R) is true.
  • B
    (A) is true but (R) is false.
  • C
    Both (A) and (R) are true and ( $\mathbf{R}$ ) is the correct explanation of $(\mathbf{A})$.
  • Both (A) and (R) are true but ( $\mathbf{R}$ ) is not the correct explanation of (A).

Answer

Correct option: D.
Both (A) and (R) are true but ( $\mathbf{R}$ ) is not the correct explanation of (A).
(D)
Sol.
(A) : True
(B) : True but not correct explanation

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