- #1

- 25

- 0

## Homework Statement

Calculate the veolcity of a proton of energy 0.12 keV

proton mass = 1.7 x 10^-27

## Homework Equations

## The Attempt at a Solution

I thought...

0.12 keV = 120 eV

120/1.60 x 10^-19 = 7.5 x 10^20 J

E = 0.5mv^2

sqrt(2E/m) = v

but I'm getting something to x 10^23 so its obviously wrong.

its A-Level physics so shouldnt be a really complex answer...

Going wrong somewhere but cant work it out. Probably where I divided by the charge of an electron?

Any help appreciated.

James