a photo sensitive metal is not emitting photo-electrons when irradiated it will do so when threshold

Stopping potential for photo electrons

The threshold wavelength for a photosensitive metal plate is 5000 Å. Photoelectrons will be emitted from it if it is irradiated by light from a

A Photo sensitive material would emit electrons if excited by photons beyond a threshold. To overcome the threshold, one would increases -

The maximum energy of emitted photo electrons is measured by

The mass of a photo electron is

A photon of wavelenth 3000 A strikes a metal surface, the work function of the metal being 2.20eV . Calculate (i) the energy of the photon in eV(ii) the kinetic energy of the emitted photo electron and (iii) the velocity of the photo electron.

Monochromatic radiation emitted when electron on hydrogen atom jumps from first excited to the ground state irradiates a photosensitive material The stopping potential is measured to be 3.57 V The threshold frequency of the material is

When green light is incident on the surface of metal , it emits photo - electrons but there is no such emission with yellow colour light. Which one of the colours can produce emission of photo - electrons ?