The treshold wavelength for photoelectirc emission from a material is `4800 Å` Photoelectrons will be emitted from the material , when it is illuminated with light from a

Options

A. A)40 W blue lamp
B. B)40 W green lamp
C. C)100 W yellow lamp
D. D)1000 W green lamp

Answer

A

Explanation

The wavelength of blue light is `4800 Å` , so material will emit photoelectrons when it is illuminated with light from a 40 W blue lamp .