Set-up and procedure
The experiment is set up as in Fig. 1. The coils of the electromagnet
are connected in series and are connected to the
alternating voltage output of the power unit via an ammeter, a
switch and a bridge rectifier. For the first two parts of the
experiment, a fixed voltage of 12 V a. c. is selected and the
associated current IM in the coils is measured.
The conductor loops are connected via two light flexible metal
stripes, first of all to a distributor, and then via an ammeter to
the direct voltage output of the supply unit. The distance between
the metal strips should be as large as possible and they
should only sag slightly, so that no forces from the magnetic
field act on them.