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A photon of wavelength 0.79159 nm strikes a free electron that is initially at rest. The photon is scattered straight backward. What is the speed of the recoil electron after the collision?
v =
1 Answer
- az_lenderLv 79 hours ago
Initial momentum of the photon is h/lambda = 8.3705 x 10^(-25) kg*m/s.
As the photon is scattered straight backwards, it imparts twice this momentum to the electron.
v = p/m = (1.6741 x 10^(-24) kg*m/s)/(9.109 x 10^(-31) kg) = 1.838 x 10^6 m/s.
Not necessary to consider relativity, as this is less than 1% of c.