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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): The wave theory of light successfully explains the existence of a threshold frequency in the photoelectric effect. Reason (R): According to the wave theory, light of any frequency should eventually cause electron emission from a metal surface if the intensity is high enough and sufficient time is g

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

D. Assertion (A) is false but Reason (R) is true

Step-by-step solution

Assertion (A) is false because the wave theory of light fails to explain the existence of a threshold frequency. According to classical wave theory, energy is absorbed continuously by the electrons, so any frequency of light should eventually eject an electron. Reason (R) is true. The wave theory predicts that even for low-frequency light, if the intensity is sufficiently high, electrons will eventually accumulate enough energy to escape the metal surface. This contradicts the experimental observation that no emiss

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