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NEETPhysicsDual Nature of Matter

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): If the frequency of incident light is less than the threshold frequency, halving the distance between a point light source and a photoelectric metal will not produce any photoelectric current. Reason (R): The intensity of light from a point source is inversely proportional to the square of the dist

Options

  1. ABoth (A) and (R) are true and (R) is the correct explanation of (A).
  2. BBoth (A) and (R) are true but (R) is not the correct explanation of (A).
  3. C(A) is true but (R) is false.
  4. D(A) is false but (R) is true.

Correct answer

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

Step-by-step solution

Assertion (A) is true: For photoelectric emission to occur, the incident frequency must be strictly greater than the threshold frequency ( > ₀ ). If Reason (R) is true: For a point source, intensity I 1 r^2 . Halving the distance increases the intensity by four times. However, (R) is not the correct explanation of (A). The correct explanation for (A) is that the energy of individual photons ( h ) is less than the work function of the metal, so they cannot eject electrons, even though the total number of incident ph

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