Electron acceleration and kinetic energy

[wakejosh]

Homework Statement

an electron in a TV picture tube is accelerated through a potential difference of 10 Kv before it hits the screen. What is the kinetic energy of the electron in electron volts when it hits the screen?



ok, so i know how to work this for Joules and i get: 1.6 x 10 ^-15 J. Now i am not so sure about converting this to eV, I looked up a conversion on the internet and found: 1 eV= 1.6 x 10^-19 J so is it correct to say that the answer is:

1.0 x 10 ^4 eV

any help is appreciated.

 

[neutrino]

Yep. You can also write it as 10 KeV.

 

[m2003]

Yes, your answer is correct. To convert from joules to electron volts, you need to divide by the conversion factor of 1.6 x 10^-19. So, 1.6 x 10^-15 J divided by 1.6 x 10^-19 J/eV gives you 1.0 x 10^4 eV. This means that the kinetic energy of the electron when it hits the screen is 10,000 electron volts.