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Threshold wavelength for photoelectric e...

Threshold wavelength for photoelectric emission from a metal surface is 5200 A. Photoelectrons will be emitted when this surface is illuminated with monochromatic radiation from

A

1 W IR lamp

B

50 W UV lamp

C

50 W IR lamp

D

10 W IR lamp.

Text Solution

Verified by Experts

The correct Answer is:
B
For photoelectric emission the wavelength of incident light should be smaller than threshold wavelength. The wavelength of ultraviolet light is about `4xx10^(-7)m` (4000 A).
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