Question

if light photons are incident on a photosensitive metal of work function 2.1ev and the maximum kinetic energy of the photoelectron emitted is 1.9ev, the energy of incident photons is?​

Answer 1

Explanation:

Based on the wave model of light, physicists predicted that increasing light amplitude would increase the kinetic energy of emitted photoelectrons, while increasing the frequency would increase measured current.

Contrary to the predictions, experiments showed that increasing the light frequency increased the kinetic energy of the photoelectrons, and increasing the light amplitude increased the current.

Based on these findings, Einstein proposed that light behaved like a stream of particles called photons with an energy of \text{E}=h\nuE=hνstart text, E, end text, equals, h, \nu.

The work function, \PhiΦ\Phi, is the minimum amount of energy required to induce photoemission of electrons from a metal surface, and the value of \PhiΦ\Phi depends on the metal.

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