Light of wavelength is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is . Find the work function of the material from which the emitter is made.

Wavelength of light produced by the argon laser is given as

Stopping potential of the photoelectrons is given as

Therefore,

Planck’s constant,

Charge on an electron,

Speed of light,

Following is the relation for the work function Using Einstein’s photoelectric effect:

of the material of the emitter as:

=

Therefore, the work function of the material with which the emitter is made is .