012-03760E
Coulomb Balance
3
The Coulomb Balance and the included accessories are
shown in Figure 2.
Equipment
(The Coulomb Balance and the slide assembly should be
shipped with one of the conductive spheres unattached.
See the
Setup
section of this manual.)
Additional Equipment Recommended:
A stable kilovolt power supply for charging the
spheresAny electrostatic charger can be used to
charge the spheres, but a power supply lets you
replenish the charge to a fixed value throughout an
experiment. Ideally the supply would have a
momentary power on button so that you can
conveniently turn it off whenever you are not
charging the spheres.
Figure 2. The Coulomb Balance
charging probe
slide assembly
allen wrench for the slide
assembly
conductive sphere on insulating
thread
torsion wire
clamp
COULOMB
BALANCE
magnetic
damping arm
index arm
calibration
support tube
toolbox with:
one 50 mg mass
two 20 mg masses
one hex key
torsion wire
retainer
(pendulum)
coupling
Plate
spare torsion wire
(3 meters)
ä
NOTE:
The balance may
be shipped with the copper
rings unattached.
An electrometer and Faraday ice pail (such as
PASCO Models ES-9054A and ES-9058) for
accurately measuring the charge on the spheres.
A spring balance capable of measuring a force of
approximately 4 newtons (400 gram mass). This is
not necessary for the experiment itself, but is helpful
in setting the tension of the torsion wire.
