# Larmor frequency

1. Oct 25, 2005

Can someone please explain Larmor frequency to me? (like how the equation w=q*B/2m is derived?) I would greatly appreciate it!!

2. Oct 25, 2005

### Tide

The Larmor frequency aka the "gyrofrequency" is the frequency with which charge particles orbit in a magnetic field. It directly from the solution of the equations of motion:

$$\frac {d\vec v}{dt} = \frac {q}{m} \vec v \times \vec B$$

I don't think you meant to include the factor of 1/2.

The term is also used to denote the rate of precession of a magnetic moment in a magnetic field such as an atomic nucleus. I gathered you meant the "gyrofrequency" from the form you displayed.