Question
Show that it is not possible for a photon to be completely absorbed by a free electron.
✓
Answer
If the i undergoes an elastic collision with a photon. Then applying energy conservation to this collision.
We get,
$\frac{\text{hc}}{\lambda}+\text{m}_0\text{c}^2=\text{mc}^2$and applying conservation of momentum
$\frac{\text{h}}{\lambda}=\text{mv}$Mass of e
$=\text{m}=\frac{\text{m}_0}{\sqrt{1-\frac{\text{v}^2}{\text{c}^2}}}$from above equation it can be easily shown that
V = C
V = 0
both of these results have no physical meaning hence it is not possible for a photon to be completely absorbed by a free electron.
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