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प्रश्न
A photon of energy hv is absorbed by a free electron of a metal with work-function hv − φ.
विकल्प
The electron is sure to come out.
The electron is sure to come out with kinetic energy hv − φ.
Either the electron does not come out or it comes our with kinetic energy hv − φ.
It may come out with kinetic energy less than hv − φ.
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उत्तर
It may come out with kinetic energy less than hv − φ.
When light is incident on the metal surface, the photons of light collide with the free electrons. In some cases, a photon can give all the energy to the free electron. If this energy is more then the work-function of the metal,then there are two possibilities. The electron can come out of the metal with kinetic energy hv − φ or it may lose energy on collision with the atoms of the metal and come out with kinetic energy less than hv − φ. Thus, it may come out with kinetic energy less than hv − φ.
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संबंधित प्रश्न
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The work function for the following metals is given:
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The graph shows the variation of photocurrent for a photosensitive metal
- What does X and A on the horizontal axis represent?
- Draw this graph for three different values of frequencies of incident radiation ʋ1, ʋ2 and ʋ3 (ʋ3 > ʋ2 > ʋ1) for the same intensity.
- Draw this graph for three different values of intensities of incident radiation I1, I2 and I3 (I3 > I2 > I1) having the same frequency.
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