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The surface of a metal of work funcation...

The surface of a metal of work funcation `phit` is illumicated by light whose electric field component varies with time as `E = E_(0) [1 + cos omegat] sinomega_(0)t`. Find the maximum kinetic energy of photonelectrons emitted from the surface.

Text Solution

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The given electric field component is `e = E_(0)sin omega_(0) t + E_(0) sinomegat cos omegat`
`= E_(0)sin omega_(0)t + (E_(0))/(2)[sin (omega_(0) + omega) t + sin(omega_(0) - omega)t]`
`:.` The given light comprises three different frequencies viz. `omega, omega_(0) + omega, omega_(0)-omega`
the maximum kinetic energy will be due to most energetic photon. `:. KE_(max) = hv - phi = (h(omega + omega_(0)))/(2pi) - phi (:' omega = 2piv` or `v = (omega)/(2pi)`
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