##### Physics question 4 hw 20

 Physics Tutor: None Selected Time limit: 1 Day

In the photoelectric effect, the maximum speed of the electrons emitted by a metal surface when it is illuminated by light depends on which of the following? I) Intensity of the light II) Frequency of the light III) Nature of the photoelectric surface

1. III only

2. I and II only

3. I, II, and III

4. II and III only

5. I only

Jul 14th, 2015

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According to Einstein's photoelectric equation, the maximum kinetic energy for the liberated electrons is

$K_{max} = hf-\phi$

where $\phi$ is the work function of the metal.

Therefore, Kmax is independent of the intensity of light. It does depend on the frequency of the light, and the nature of the photoelectric surface (which determines $\phi$).

ANSWER:  4. II and III only

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Jul 14th, 2015

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Jul 14th, 2015
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Jul 14th, 2015
May 26th, 2017
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