Objective: Demonstrate the superposition of magnetic fields in a vacuum
The absence of interference when magnetic fields are superposed in a vacuum is demonstrated using a
Braun tube. This is done by observing the displacements of the focused spot on the fluorescent screen
of the tube. The experiments can be extended to include alternating magnetic fields with identical and
different frequencies. The Lissajous’ figures observed on the screen depend critically on the relation
between the frequencies of the two magnetic fields and on their phase relation.