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Light coming from a discharge tube fille...

Light coming from a discharge tube filled with hydrogen falls on the cathode for the photoelectric cell. The work function of the surface of cathode is `4eV`. Which one of the following values of the anode voltage (in volts) with respect to the cathode will likely to make the photo current zero?

A

`-4`

B

`-6`

C

`-8`

D

`-10`

Text Solution

Verified by Experts

The correct Answer is:
D
Maximum photon energy `= 13.6 eV ("emitted")`
So `K_(max) = 13.6 - 4 = 9.6 eV`
Hence stopping potential is `- 9.6 V`
So `- 10 V` can stop
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