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Statement - 1: A metallic surface is irradiated by a monochromatic light of frequency ν > ν0 (the threshold frequency). The maximum kinetic energy and the stopping potential are Kmax and V0 respectively. If the frequency of the incident on the surface is doubled, both the Kmax and V0 are also doubled. Statement - 2: The maximum kinetic energy and the stopping potential of photoelectrons emitted from a surface are linearly dependent on the frequency of incident light.

1. Statement -1 is true, Statement -2 is true; Statement -2 is the correct explanation of Statement -1.
2. Statement -1 is true, Statement -2 is true; Statement -2 is not the correct explanation of Statement -1.
3. Statement -1 is false, Statement -2 is true.
4. Statement -1 is true, Statement -2 is false.

Correct answer: Statement -1 is false, Statement -2 is true.

Solution

Statement -1 is incorrect because while the maximum kinetic energy of photoelectrons increases with frequency, it does not double when the frequency is doubled; instead, it increases according to the equation Kmax = h(ν - ν0). Statement -2 is correct as both Kmax and the stopping potential are indeed directly proportional to the frequency of the incident light.

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