# Mass of an electron

1. Jan 23, 2007

### greze9

1. The problem statement, all variables and given/known data

Using Helmholtz coils we found the relationship between magnetic force and mass and therefore coming up with the mass of the electron, but im so confused on how the process actually works in relation to the strength of the current in proportion to the strength of voltage.

2. Relevant equations

F = Bev
Bev = mV^2 / r
½mv^2 = eV
e/m = 2V / B^2r^2
B = 8μ0N x I
√125 a
e/m = (1.95/ μ0 x a^2/N^2) 2V/ I^2r^2 =(5.18 x 10^7) V/ I^2r^2; or, in simpler terms:
e/m = K x V/ I^2r^2
: m = e/k x I^2r^2 / V
e/k = 1.602 x 10-19/ 5.18 x 107 = 3.09 x 10^-27. Therefore, m = 3.09 x 10^-27 I^2r^2 / V.

these are the equations we ended up producing and therefore using...

3. The attempt at a solution

2. Jan 24, 2007

### Chi Meson

We're gonna need a question. It's very tedious to try to give a full lecture through this medium. Try to be more specific as to where you get confused.

For starters, do you know what the first three equations your list "say"?