## Calculating kinetic energy of an emitted electron [ENDORSED]

Toru Fiberesima 1L
Posts: 63
Joined: Fri Apr 06, 2018 11:02 am

### Calculating kinetic energy of an emitted electron

I'm wondering how you go about calculating the kinetic energy of an ejected electron when you are only given the speed at which it is ejected. What would you would put for mass of electron in the KE equation.

Thanks

ErinKim1I
Posts: 31
Joined: Fri Apr 06, 2018 11:03 am

### Re: Calculating kinetic energy of an emitted electron  [ENDORSED]

the mass of an electron is a constant (9.11x 10^-31 kg).

LilianKhosravi_1H
Posts: 32
Joined: Fri Apr 06, 2018 11:03 am

### Re: Calculating kinetic energy of an emitted electron

yes the mass is a constant and is on the cover page of the tests so you don't have to worry about memorizing it.

danielruiz1G
Posts: 62
Joined: Fri Apr 06, 2018 11:04 am

### Re: Calculating kinetic energy of an emitted electron

The mass of an electron is a constant that you use in the equation for kinetic energy the only other way that you have to worry about mass is when it's asking for the energy of a molecule or atom where you would them have to use the periodic table to find its mass.