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Using Einstein’s photoelectric equation, if the kinetic energy of photoelectrons emitted from a metal is plotted against the frequency of the incident light, the resulting graph is a straight line. The slope of this line

1. varies with both the light intensity and the metal surface
2. varies only with the intensity of the incident radiation
3. depends on the particular metal used
4. is identical for every metal and does not depend on the radiation intensity

Correct answer: is identical for every metal and does not depend on the radiation intensity

Solution

The slope of the graph represents Planck's constant, which is a fundamental constant of nature and does not change with different metals or the intensity of light. This means that regardless of the metal used, the relationship between kinetic energy and frequency remains consistent, leading to the same slope.

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