### Find the effect!

Hab hier ein Zitat aus einer muenlichen Pruefung in Physik und ich moechte gerne, dass ihr erratet um was es dabei geht :

A particle wich moves and has a own magnetic momentum and moves in an electric field. And this magnetic momentum interacts with the electric field. Because you can, with a Lortez transformation, show that in the system of the electron, the electric field transforms into a magnetic field. And this magnetic field influences the magnetic momentum of the electron, or the particle, it is not just applicable for electron, it's any particle with magnetic moment.
Viele Gruesse
$\vec b^{ \underline{ \tilde l \underline a}} b\!\!\!/ ^{\hat l \underline{\breve u} \overline{ \dot b \vec{ \ddot b b^\prime}}}$