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A beam of ligth having frequency v is in...

A beam of ligth having frequency `v` is incident on an initially neutral metal or work function `phi(hv gt phi)`. Then

A

all emitted photoelectrons have kinetic energy equal to `(hv gt phi)`

B

all free electrons in the metal, that absorb photons of energy `hv` completely, may not be ejected out of the metal.

C

after being emitted out of the metal, the kinetic energy of photoelectrons decreases continuously as long as they are at a finite distance from metal .

D

the emitted photo electrons move with constant speed after escaping from the electric field of metal.

Text Solution

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The correct Answer is:
B, C
Some electrons in the interior of the metal may use all the energy absorbed by them in coming on to the surface hence those can't come out.After being emitted electrons get retarted due to positive potential devolped on the metal (due to loss of electrons)
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