# Homework Help: Magnitude of magnetic force?

1. Feb 15, 2009

### kristibella

1. The problem statement, all variables and given/known data
An electron travels at a speed of 2.0x10^4 m/s through a uniform magnetic field whose magnitude is 1.2x10^-3 T. What is the magnitude of the magnetic force on an electron if its velocity and magnetic field:
a. are perpendicular?
b. make an angle of 45 degrees?
c. are parallel?
d. are exactly opposite?

2. Relevant equations
F = qvB(sin $$\vartheta$$

3. The attempt at a solution
I haven't made any attempts because there is no q value...

2. Feb 15, 2009

### Delphi51

It is an electron - look up the charge on an electron.
Soon you will have it memorized!

3. Feb 15, 2009

### kristibella

...I'm slightly embarrassed because I completely looked over that detail. Thank you for pointing that out.