Author: BIGS 2001 (C. Bluck, J. Gans, A. Gleixner, Prof. W. Heimbrodt, Dr. Maddocks, S. Stallmann)
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Without magnetic field
Electrons emerge from the glowing cathode (-). On their path to the anode (+), they are accelerated by the potential difference applied. The electrons move in a straight line.
With magnetic field
Interaction with a magnetic field (such as the field of a coil) produces a curvature in the previously straight path of the electrodes. The magnetic field, or more precisely the Lorentz force, forces the electrodes onto a circular path perpendicular to the magnetic field force lines.