# Electron in a magnetic field

1. Apr 10, 2014

### googlyeyes

1. The problem statement, all variables and given/known data

An electron is accelerated from rest through a potential difference V and then enters a uniform magnetic field oriented perpendicular to its path. The field deflects the particle into a circular arc of radius R. If the accelerating potential is tripled to 3V, what will be the radius of the circular arc?

2. Relevant equations

?

3. The attempt at a solution

The answer is √3 R, just not sure how to get there

2. Apr 10, 2014

### Tanya Sharma

1. What is the relationship between Electric field and potential difference V ?
2. What is the force on the electron as it moves through the region of potential difference V?
3. Find the relationship between the velocity of the electron just as it is about to enter the magnetic field , and the potential difference V ?
4.Find the relationship between the velocity of the electron in the magnetic field , and the radius of the circular arc.