(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

In Compton scattering,how much energy must the photon have in order for

the scattered electron to achieve relativistic velocity?

2. Relevant equations

Compton scattering formula: $$λ'-λ=\frac{h}{mc}(1-cosθ)$$

##E=\frac{h}{λ}##,conservation of mass and momentum,possibly Lorentz transformations for velocity and kinetic energy?

3. The attempt at a solution

My train of thought goes like this:

Assume that θ=90°. That gives us ##λ'-λ=\frac{h}{mc}##.

##λ'-λ## can easily be turned into ##E'-E## using ##E=\frac{h}{λ}##.

Using law of conservation of energy we solve for the kinetic energy of the scattered electron

Since we now know the electron's kinetic energy we can calculate its speed.

My problem lies with my first assumption.I don't know if it's correct. It was made after a hint that my professor made that we should use big angles.

Please note that I don't study physics in English so some things might require clarification.

Thank you for your time.

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# Homework Help: Electron velocity after Compton Scattering

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