A) 1 W IR lamp
B) 50 W UV lamp
C) 50 W IR lamp
D) 10 W IR lamp
Correct Answer: B
Solution :
For photoelectric emission to take place the wavelength of incident light must be less than the threshold value which is given as \[5200{\AA}.\]. The wavelength of infra-red light \[=7800{\AA}\] The wavelength of ultra-violet light\[=4000{\AA}\] Thus, it is obvious that wavelength of UV radiation is less than the threshold value. Hence, it can emit photoelectrons from the surface of metal.You need to login to perform this action.
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