PHYCS 102 Lab.
Date:
Student Name:_____________________
ID No. :_______________
Student Partners:___________________
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Sec. : (______)
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Experiment 2- The Parallel Plates Capacitor
1- Experiment Objectives
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2- Apparatus:
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3- Brief Theoretical Introduction:
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4- Data and Data Analysis:
4.1 (Part I): Variation of the electric field (E) with the plates’ separation (d)
E
at constant potential difference (ΔV), (E =ΔV/d)
Electrometer
 Follow the manual instructions and measure the electric field E
Light is
ON
between the plates as you vary (d) while keeping the potential
+
difference between the plates constant.
d
(Note: use the middle range on the electrometer)
 Record the distance between the plates (d) and readings of the
V
voltmeter that is connected to the electrometer in the following table:
Measured potential difference between the plates ΔV= 170 ………(V)
Electric field conversion factor: 1V for each 1000V/m
d ………( )
VElectrometer (V)
E( )
1/d ( )
0.050
0.060
0.070
0.080
0.090
0.100
 Plot E vs. d on a graph paper and describe the variation.
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 Plot E vs. 1/d on a graph paper.
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 Find the slope of the graph E vs. 1/d. (show your calculations).
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 Use the slope of the graph to find the potential difference between the plates (ΔV), and calculate the
percentage difference in your result.
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4.2 (Part II): Variation of the electric field (E) with the potential difference (ΔV) when the
plates’ separation (d) is kept constant, (ΔV = Ed).
 Follow the manual instructions and measure the electric field E between the plates as you vary the
electric potential (ΔV) while keeping the distance between the plates constant.
(Note: again use the middle range on the electrometer )
 Record the voltage across the plates and readings of the voltmeter that is connected to the electrometer
in the following table:
Distance between the plates d= 0.060 ……..(m)
Electric field conversion factor: 1V for each 1000V/m
ΔV ….…(V)
VElectrometer (V)
E(
)
170
140
110
80
50
 Plot E vs. ΔV on a graph paper and describe the variation.
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 Find the slope of the graph (show you calculations).
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 Use the slope of the graph to find the distance between the plates (d), and calculate the percentage
difference in your results.
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5- Conclusions
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6- Questions
Calculate the absolute error in electric field (E) if electric potential ΔV=(150 ± 1)V, d= (0.050 ± 0.001 )m
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