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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 on a photosensitive metal is doubled (keeping it above the threshold frequency), the maximum kinetic energy of the emitted photoelectrons becomes more than double its initial value. Reason (R): According to Einstein's photoelectric equation, the work function of a

Options

  1. ABoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
  2. BBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
  3. CAssertion (A) is true but Reason (R) is false.
  4. DAssertion (A) is false but Reason (R) is true.

Correct answer

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

Step-by-step solution

According to Einstein's photoelectric equation, the maximum kinetic energy is given by K₁ = h - , where is the work function of the metal. When the incident frequency is doubled to 2 , the new maximum kinetic energy becomes: K₂ = h(2 ) - We can rewrite this expression in terms of the initial kinetic energy K₁ : K₂ = 2h - 2 + K₂ = 2(h - ) + K₂ = 2K₁ + Since the work function is a positive constant for a given metal, it follows that K₂ > 2K₁ . This means the maximum kinetic energy more than doubles. Therefore, Assert

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