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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 in a photoelectric experiment is doubled (keeping intensity constant), the stopping potential becomes more than double. Reason (R): The work function of the metal surface remains unchanged when the frequency of incident light is varied. In the light of the above s

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 stopping potential V₁ for an incident frequency is given by: eV₁ = h - When the frequency is doubled to 2 , the new stopping potential V₂ is: eV₂ = h(2 ) - eV₂ = 2h - We can rewrite this by substituting h = eV₁ + : eV₂ = 2(eV₁ + ) - eV₂ = 2eV₁ + 2 - eV₂ = 2eV₁ + Dividing by e , we get: V₂ = 2V₁ + e Since the work function is a positive constant, V₂ > 2V₁ . Therefore, the stopping potential becomes more than double. The Assertion (A) is true. The mathematical reaso

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