Discussion Forum

Light of wavelength  $\lambda$  which is less than threshold wavelength is incident on a photosensitive material. if the incident wavelength  is decreased so that emitted photoelectrons are moving with the same velocity, then stopping potential will

Answer:

Explanation:

According to photo electric equation,

$\frac{hc}{\lambda}$=$\phi$+E

 symbols have their usual  meaning

 E= kinetic energy

if E is constant, then $\frac {1}{\lambda}$ $\propto \phi$

If we decrease the wavelength $\lambda$  , then stopping potential $\phi$  will increase such that 

$\frac{hc}{\lambda}-\phi= constant$