Electricity
and Magnetism > Electromagnetic Induction > Induced Currents and
Forces
DCS#
5K20.30
JUMPING RING
APPARATUS
jumping ring apparatus
202-20-E6
box of rings
202-20-E6
DESCRIPTION
Apparatus consists of a coil of
wire
with
a protruding iron core. A solid aluminum or copper ring on core
will
jump when an alternating current passes through the coil. A ring
cooled in liquid nitrogen will jump higher. A split ring will not
jump. There are various other rings of different materials,
diameters,
and thicknesses to try.
Connect voltmeter to split ring to measure induced emf.
NOTES
The force depends on the phase
difference
between the induced emf and the current in the coil.
