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utkarshakash
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Homework Statement
When a photon is emitted from an atom the atom recoils. The kinetic energy of recoil and the energy of photon come from the difference in energies between the states involved in the transition. Suppose a hydrogen atom changes its state from n=3 to n=2. Calculate the fractional change in wavelength of light emitted due to the recoil.
Homework Equations
The Attempt at a Solution
Difference in energies of states = -13.6(1/4 - 1/9)
This is equal to sum of KE of recoil and energy of photon(ΔE).
[itex] \dfrac{mv^2}{2} + \delta E = -13.6 \left( 1/4 - 1/9 \right) [/itex]
From this I can find energy of photon released only if I know the velocity v.