Find the maximum magnitude of the linear momentum of a photoelectron emitted when light of wavelength 400 nm falls on a metal having work function 2.5 eV.

Given, wavelength λ =400×

Work function=2.5eV

From photoelectric equation,

Where K is kinetic energy,

h is Planck’s constant,

c is speed of light,

Ф is the work function,

is the wavelength of light.

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We also know that,

Where P is linear momentum and m is mass of electron

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