3B Scientific Gyroscope User Manual
Page 3
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3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com • Technical specifications subject to change
•
Suspend an additional weight from the axle.
•
Make the device rotate either manually or with the
help of the string.
•
The gyroscope displays precession.
•
Determine the rotational frequency f of the disc and
measure the period for one precession cycle T
P
.
•
The relation between f and T
P
is calculated using the
following equation:
D t
I =
∆
ω
E
where R is the distance from the fulcrum of the gyro-
scope axis to the point where the additional weight
m is attached.
•
Take further measurements at decreasing rotational
frequencies.
•
Plot a graph of the frequency of rotation as a func-
tion of the period of a precession cycle.
•
As an alternative to the method described above, the
moment of inertia I of the disc can also be deter-
mined from the straight line gradient a.
m g R
f
a
π
2
=
4
•
Repeat the experiment using a different added weight.
It can be determined that the precession frequency is
approximately proportional to the added mass.
5.3 Nutation
•
The aim of the experiment is to demonstrate nuta-
tion and to study the interdependence between nu-
tation frequency and frequency of rotation of the
disc.
•
Set up the gyroscope as shown in Fig. 3 and balance
it.
•
Make the disc rotate, either manually or with the help
of the string.
•
A slight lateral push to the spinning axis of the gyro-
scope will initiate nutation.
•
In order to make a quantitative evaluation of the
experiment, determine the period of a suitable
number of nutation cycles.
Fig. 2: Precession
•
Subsequently measure the period of rotation of the
disc.
•
Make further measurements at slower disc frequen-
cies
•
Plot a graph of the nutation frequency as a function
of the frequency of rotation of the disc.
•
The nutation frequency is proportional to the rota-
tion frequency.
5.4 Cancellation of gyroscopic forces
•
As shown in Fig. 4, slide a second disc and counter-
weight along the axis and secure with the locking
ring.
•
Balance the gyroscope.
•
Attach the additional weight.
•
Manually rotate the discs. Make sure they rotate in
the same direction. To see the direction of rotation
more clearly, you can glue a piece of white paper
onto each disc.
•
Demonstrate precession and nutation.
•
Now wind each end of the string in opposite direc-
tions around a different bobbin.
•
When the string is pulled, both discs begin to rotate
in opposite directions with approximately the same
rotational speed.
•
Demonstrate the cancellation of gyroscopic forces.
Fig. 3: Nutation
Fig. 4: Cancellation of gyroscopic forces