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The anode vollage of a photocell is kept...

The anode vollage of a photocell is kept fixed . The wavelength `lambda `of the light falling on the cathode varies as follows

A

B

C

D

Text Solution

Verified by Experts

The correct Answer is:
B
With the increase in wavelength energy of the photon decreases. Therefore the KE of the electron coming out from the cathode also decreases. Due to which there will be a small decrease in plate current and once `lambda` becomes more than threshold wavelength electron will not come out from the cathode and hence current will become zero.
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ALLEN-SIMPLE HARMONIC MOTION-Exercise-04 [B]
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