# Uniform magnetic field and electric field

## Homework Statement

How would you find the period of a charged particle in an uniform electric and magnetic field?
The charged particle has velocity that is perpendicular to the magnetic and electric field (which are directed in the x-axis).

F=q(E+vxB)

## The Attempt at a Solution

In the absence of an electric field, I see that the period is given by T=2pi(m/qB). Not sure how I can find it when an electric field is present.

Hey, when you say period, do you mean that the particle is orbiting something?

I misunderstood the question, but I need to find the magnitude of the velocity after 'c' revolutions.

gneill
Mentor
What does "directed in the x-axis" mean? If you were to write the three Cartesian components of, say, the electric field vector, what might it look like?

I am lost with this question, but to go about finding the velocity at time t I think it's v=q/m (integral)[E+vxB]dt, it's just the limits of integration I'm not able to find.