6. Experiment Procedure
6.1 Setting up (see Figs. 1 and 2)
•
Attach the stainless steel rod (h) to the long stand
rod (f) and secure it.
•
Insert the air-cushion bearing unit (j) in a hole in
the long stand rod (f) and tighten the locking
screw.
•
Attach the
(n) to a long supporting rod (f)
pulley
and secure it with a locking screw.
•
Attach the start/stop unit to the short supporting
tube (e), secure it, and slide it onto the stainless
steel rod (h).
Before completing the set-up and beginning the
experiment, the rotating system must be made level.
•
Place the levelling disc in the circular recess of the
air-cushion bearing unit.
•
Attach the tube from the compressor to the inlet
connector (k).
•
Connect the compressor to the mains and switch
it on.
•
The two adjustment screws (g and m) allow
inclination with respect to the horizontal to be
adjusted in two planes (see Fig. 3).
The levelling is satisfactory when the levelling disc
spins around evenly over the surface of the air-bearing
unit.
•
Place the rotating disc (i), together with the
tranverse and the multiple pulley, on the air-
cushion bearing unit (j).
•
Push the start/stop unit up to the rotating disc
and secure it with the locking screw. The foam
pad of the pointer (a) should be in slight contact
with the edge of the rotating disc.
Fig. 1 Set-up for the start/stop unit: a pointer, b starting
lever, c sockets for starter, d bracket for laser reflection
sensor, e short stand rod
Fig. 2 Set-up of the rotating system: f long stand rod, g and
m levelling screws, h stainless steel rod,
i rotating disc, j air-cushion bearing unit, k tube inlet,
l transverse beam with graduated pulley and additional
weights, n pulley
Fig. 3 Levelling the rotating system
6.2 Regulating the air supply
•
Use only the valve (p) to regulate the airflow.
Fig. 4 Air supply controls: o airflow generator (compressor),
p valve, q tube
3