| E&M
> Electromagnetic Induction > Eddy Currents |
DCS#
5K20.40 |
EDDY CURRENT
LEVITATOR
-
APPARATUS
neodymium disk magnet on
flexible arm
|
202-20-E |
aluminum disk
|
202-20-E |
motor
|
202-20-E |
DC power supply
|
202-08-D
|
video
camera
|
202-09-D
|
DESCRIPTION
- The magnet hovers about a centimeter
above the spinning metal disk. The relative motion
between the magnet and disk produces eddy currents in the disk whose
magnetic field repels
the magnet.
Move the magnet toward the center of
the disk to show that the height of the magnet depends on the speed of
the aluminum.
- NOTES
The motor requires at
most 27.5 V and 3 A. The disk's tangential velocity near the edge
with the motor set to 5 V is sufficient to levitate the magnet.
Magnetic damping
can be a problem when starting up the motor, it may be necessary to
lift the magnet out of the way initially.