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Given below are two statements: Statement I : Out of microwaves, infrared rays and ultraviolet rays, ultraviolet rays are the most effective for the emission of electrons from a metallic surface. Statement II : Above the threshold frequency, the maximum kinetic energy of photoelectrons is inversely proportional to the frequency of the incident light.

1. Statement I is true and Statement II is true.
2. Statement I is true and Statement II is false.
3. Statement I is false and Statement II is true.
4. Statement I is false and Statement II is false.

Correct answer: Statement I is false and Statement II is true.

Solution

Ultraviolet rays are indeed effective for the emission of electrons, but they are not the only type; microwaves and infrared rays are less effective, making Statement I misleading. Statement II is accurate because, according to the photoelectric effect, the maximum kinetic energy of emitted electrons increases with frequency, not inversely.

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