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## Homework Statement

I need to figure out the energy, rest mass, speed, wavelength and momentum of a 2.2 eV electron. Thats all it says.

## Homework Equations

Ek = 1/2mv^2

## The Attempt at a Solution

I dont understand what 2.2 eV is. The kinetic energy?

This converts to 3.52x10^-19 J

Rest mass should be 9.11x10^-31. Or do I use E=mc^2? Why or why not?

No idea how to find speed, which I need to calculate wavelength and momentum. I could use Ek= 1/2mv^2 because the electron will not be travelling close to the speed of light, but I feel like this is not the way you SHOULD calculate it. There has to be another way.