Calculating Wavelength of Photons to Produce 30 keV Electrons

[KingNothing]

Homework Statement

56. What wavelength of photons are needed to produce 30 keV electrons in a compton scattering?

Homework Equations

$$E=\frac{hc}{\lambda}$$

The Attempt at a Solution

This question throws me off because I was under the impression that compton scattering didn't produce any electrons, but simply deflected them. It also confuses me because I assume it's asking "What photons will produce electrons with total energy of 30-keV?" However, electrons have that much energy in rest mass alone.

Can anyone interpret this better?

 

[rock.freak667]

Not sure what compton scattering is, but I'd find the velocity of the electrons from their energy and and then use the de Broglie wavelength formula


$$\lambda = \frac{h}{mv}$$

 

[KingNothing]

With all due respect, your suggestion does not make sense in the context of what we've discussed. We've discussed compton scattering, and have not discussed de Broglie wavelengths.

 

[kuruman]

Here is my interpretation:

Assume that you have an electron at rest. An incoming photon Compton scatters off it and the electron acquires a kinetic energy of 30 keV. What is the initial wavelength of the photon?