3B SCIENTIFIC® PHYSICS
Waltenhofen pendulum 8497500
Instruction sheet
12/06 SP
1 Slotted aluminium ring
2 Aluminium ring
3 Aluminium disc
4 Stand rod (not included within
the scope of delivery)
5 Clamp (not included within the
scope of delivery)
6 Bearing rod
7 Roll axis
8 Pendulum rod
9 Slotted clamp with knurled
screw
10 Rectangular aluminium plate
1. Description
The Waltenhofen pendulum is used to demonstrate
the working of an eddy current brake and its effect.
A pendulum rod is attached by means of a magnet to
a bearing rod. Four different pendulum bodies are
provided for the experiments. A heavy rectangular
aluminium pendulum disc oscillates between the
poles of an electromagnet that is switched off. When
the electromagnet is switched on, the oscillating
motion of the aluminium disc ceases within a very
short time, owing to the magnetic field generated by
the electromagnet. If the disc/plate is slotted, then
the time required for the oscillating motion to stop is
extended, i.e. there is a strong reduction in the braking effect.
2. Scope of delivery
1 Pendulum rod with bearing rod and slotted
clamp
4 Aluminium pendulum discs:
Rectangular plate and slotted rectangular plate
Disc
Ring
Slotted ring
3. Technical data
Rectangular plate: 65 mm x 86 mm, 29 g
Disc: 78 mm ø, 26 g
Ring 70 mm ø, 21 g
Slotted ring: 70 mm ø, 20 g
Pendulum rod: 80 mm x 275 mm, 112 g
1
3. Experiment set-up
The following apparatus is additionally required for
conducting the experiments:
1 Stand base, 150 mm U13270
1 Stand rod, 750 mm U15003
1 Universal clamp U13255
1 Horseshoe magnet, 150 x 130 x 40 mm
3
U8497210
1 Pair of pole pieces, bored 8497200
1 Pair of yokes, 40 x 40 mm
2
8497181
2 Coils, number of turns 1200 8497440
1 DC power supply unit 16 V, 0-2.5 A 8521145
Safety experiment leads
Fig. 1: Experiment set-up of a Waltenhofen pendulum
Elwe Didactic GmbH • Steinfelsstr. 6 • 08248 Klingenthal • Germany • www.elwedidactic.com
3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com
Technical amendments are possible.