# Motion in an Electric Field

## Uniform Electric Field (Motion Parallel to the Electric Field)

### In the previous section we looked qualitatively at uniform Electric fields. By combining this understanding with the equations of motion calculations of the previous unit, it is possible to describe mathematically how a charged particle will move in an Electric field. ## Example 3 - ## Non-Uniform Electric Field ( Head-On approach )

### In the above situations, the uniform Electric field allowed simple calculations based using the equations of motion. If, However, a non-uniform field is present, it becomes much easier to characterise the situation as an energy conservation problem. ### As the Alpha particle approaches, it experiences a Force opposing its motion. This Force causes the Alpha particle to lose Kinetic Energy. This Ek is converted into Electrostatic Potential Energy, giving a point of closest approach when Ek = 0 and Ep= max :- ### By conservation of Energy, a value for closest approach can be obtained :- 