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A caesium photocell , with a steady pote...

A caesium photocell , with a steady potential difference of `60 V` across , is alluminated by a bright point source of light `50 cm` away. When the same light is placed `1 m` away the photoelectrons emitted from the cell

A

are half as previous

B

are one quarter as previous

C

each carry one quarter of their previous energy

D

eacy carry one quarter of their previous momentum

Text Solution

Verified by Experts

The correct Answer is:
B
Intensity of light falling on the caesium photocell in the second case will be `((50^(2))/(100^(2))=(1)/(4))`
one fourth of the previous value.
According to the laws of photoelectricity, number of photo-electrons emitted will be proportional to the intensity of light.
`therefore` Number of photo-electrons emitted in the second case is one quarter of the previous case.
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