Electron and Photon Field Effect
Fire an electron and a photon into the same electric and magnetic fields and only one of them bends. This simulation puts them side by side, isolating what charge does and what it does not.
How to use this simulation
- Fire electrons and photons into the field region
- Switch between electric and magnetic fields and vary their strength
- Change the particle's entry speed and direction
What to look for
- The photon path stays perfectly straight in both field types
- The electron follows a parabola in an electric field and a circular arc in a magnetic one
- Reversing the field reverses the electron's deflection but changes nothing for the photon
The physics behind it
An electron carries charge, so it feels an electric force qE and, when moving, a magnetic force qvB perpendicular to its velocity. A photon is uncharged, so both fields leave it untouched and it travels straight through. The comparison sharpens the distinction between a charged particle and a quantum of the electromagnetic field itself.