Particle in E and B Fields

This interactive simulator explores Particle in E and B Fields in Electricity & Magnetism. Lorentz force: cyclotron motion, E×B drift, trajectories in sim units. Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.

Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Electricity & Magnetism.

Key terms

  • particle
  • fields
  • particle em field
  • electricity
  • magnetism

Live graphs

How it works

A non-relativistic point charge in uniform electric and magnetic fields obeys the Lorentz force law F = q(E + v × B). In the plane perpendicular to B, this produces cyclotron motion when E vanishes, parabolic bending when B vanishes, and steady E×B drift when both are present. This simulation uses a consistent reduced unit system with scaled time so trajectories are easy to see; compare the measured |v|(t) to expectations for pure magnetic deflection (speed constant).

Key equations

m a = q(E + v × B)
ω_c = |q|B/m  ·  R = mv⊥/(|q|B)