# Relativistic Particle in Circular Orbit

#### SpaceTrekkie

1. Homework Statement
A particle of charge q and rest mass m0 moves in a circular orbit of radius R and angular frequency w in a uniform magnetic field b in the z direction: Find b in terms of R,q , m0, and w.

2. Homework Equations
b = (1/c) v X e and v = w/R and e = not sure. My problem is that all of my equations for e have a gamma factor (lorentz factor) in them, and I don't think i need that. So I think I am using the wrong equations.

3. The Attempt at a Solution
I got that v = w/R
and if I do indeed use gamma i have gamma(u) = (1-w^2R^2/c^2)^-(1/2)

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#### tiny-tim

Homework Helper
Hi SpaceTrekkie!

(have an omega: ω Ω and a gamma: γ and try using the X2 tag just above the Reply box )
I got that v = w/R
erm … look at the dimensions …

v = L/T, R = L, ω = 1/T: v = ωR

use good ol' Newton's second law … force = mass times centripetal acceleration

#### SpaceTrekkie

ooo ok, I was missing the part about that it will equation to F=ma. Ahh I feel dumb now. Thanks for your help!!

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