The threshold wavelength for photoelectric emission from a material is – McqOptions

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1.	The threshold wavelength for photoelectric emission from a material is 5200 Å. Photo-electrons will be emitted when this material is illuminated with monochromatic radiation from a [IIT JEE 1982; MP PMT 1992; MP PET 1999; UPSEAT 2001; KCET 2004; J & K CET 2004; BHU 2004]
A.	50 watt infrared lamp
B.	1 watt infrared lamp
C.	50 watt ultraviolet lamp
D.	1 watt ultraviolet lamp
Answer» E.

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