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The threshold wavelength for photoelectr...

The threshold wavelength for photoelectric emission from a
material is `5200 Å`. Photoelectrons will be emitted when this material is
illuminated with monochromatic radiation from a
(a) 50 W infrared lamp
(b) 1 W infrared lamp
(c ) 50 W ultraviolet lamp
(d) 1 W ultraviolet lamp
.

A

50 watt infrared lamp

B

1 watt infrared lamp

C

1 watt ultraviolet lamp

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
C
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