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Model No. ES-9080
Basic Electrostatics System
33
- ln0.01], where V
o
is the voltage of the source. Choose a signal such that the
period of the wave is at least double this charging time.
Experimental Setup
1.
Set up the circuit shown in Figure 4.3, where the resistor and the
capacitor are connected in series to the signal output generator of the
ScienceWorkshop
interface. Use a 200
P
F capacitor and a resistance of
1000
:7
he electrometer is reading the voltage across the capacitor,
and it is also connected to one of the analog channels of the Science
Workshop interface.
2.
With the DataStudio or
ScienceWorkshop
£
software, create a
display of voltage vs. time for the readings of the electrometer.
3.
Set the signal generator to produce a positive square wave of
maximum around 4 volts and of frequency 0.45 Hz. Set the signal
generator to AUTO. In this way, the signal will turn on and off as
you press Start or Stop to collect data.
4.
Start recording data. Observe the behavior of the voltage across the
capacitor on the screen. When several cycles of charging-
discharging have completed, stop the collection of data.
5.
Only one full cycle is necessary to complete all the analysis. Zoom
in to a full cycle of charge-discharge.
Analysis:
The analysis is similar to the analysis for Procedure A.
Figure 4.3: Experimental Setup
computer
electrometer
analog
channel
interface