the elastric field of an electromagnetic wave changes with the time as E=K(1+cosOmegat) cosomegat,where Omega=5xx10^(15)s_(-1), omegas^(-1) and K is constant . This radiation is incident on a sample of hydrogen atoms initially in ground state. assume that atom absorbs light as photons. Neglecting , what will be the energy of ejected electron from hydrogen . [the ionisation energy of hydrogen a tom =13.6eV and h=2pixx6.6xx10^(-16)eV-s]

the elastric field of an electromagnetic wave changes with the time as

1.	the elastric field of an electromagnetic wave changes with the time as E=K(1+cosOmegat) cosomegat,where Omega=5xx10^(15)s_(-1), omegas^(-1) and K is constant . This radiation is incident on a sample of hydrogen atoms initially in ground state. assume that atom absorbs light as photons. Neglecting , what will be the energy of ejected electron from hydrogen . [the ionisation energy of hydrogen a tom =13.6eV and h=2pixx6.6xx10^(-16)eV-s]
Answer» `0.7eV` `0.9eV` `1.4eV` `2.9eV` SOLUTION :The expression for elastric field can also be WRITTENAS `E=Kcosomegat+1/2Kcos(omega-Omega)t+1/2Kcos(omega+Omega)t`. The three terms correspond to photons of energies `(homega)/(2pi),h(omega-Omega)/(2pi)`and` h(omega+Omega)/(2pi)`. The last exceeds the ionisation energy by `2.9eV`. the difference equals to the `KE` of ejected ELECTRONS.

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