# Homework Help: Momentum of particles

1. Mar 26, 2012

### fatimae

In particle physics experiments, high energy particles are created and it desirable know the momentum of each particle. Describe how this can be done if the charge of the each particle is known

2. Mar 26, 2012

### Vorde

In physics, there is an equation $p=Bqr$
Where:
p= momentum
B= magnetic field
q= charge
r= radius of circle

What this means, is that when you have a charged particle in a magnetic field, that particle will move in a circular path of radius r. In a detector, you know the values of B and q. By performing the experiment you can experimentally find the value of r. Then you just plug in the equation and solve for p.