Download Experiment 9

Experiment 9
Frequency Dependent Circuits I
John Nosek
ENEE 206
Section 101
Lab Report 9
4/20/04
● Objective
To study the steady-state response of sinusoidally-excited RC and RL circuits as a
function of frequency.
● Equipment
-
Function Generator
Digital Oscilloscope
Breadboard
2 kΩ Resistor
0.1 μF Capacitor
10 mH Inductor
● Schematics
Figure 1
2 kΩ
+
V
~
0.1 μF
v0
_
Figure 2
2 kΩ
+
V
~
10 mH
v0
_
● Procedure
For part A, the schematic in Figure 1 was constructed and the input voltage V and
the output voltage v0 were measured on the oscilloscope. V consisted of a 5 V sine wave
and v0 was measured for the V frequencies of 100, 300, 1k, 3k, 10k, 30k, 100k and 300k
Hz. The ratio of the voltages was then computed. The time shift between V and v0 was
then measured for the V frequencies of 100, 300, 1k, 3k, and 100k Hz and the phase shift
was calculated.
For part B, the schematic in Figure 2 was constructed and again the input voltage
V and the output voltage v0 were measured on the oscilloscope. V was again a 5 V sine
wave and the voltage ratio was measured and calculated for the V frequencies of 1k, 2k,
3k, 10k, 30k, 100k, and 300k Hz. Finally, the time shift between V and v0 was measured
for the V frequencies 3k, 10k, 30k, 100k Hz and the phase shift was again calculated.
● Results
Part A
v0/V Ratio Over Different Frequencies of V
1.2
1
v0/V
0.8
0.6
Experimental Data
0.4
0.2
0
100
1000
10000
Frequency (Hz)
100000
1000000
Phase Angles of v0 for Different Frequencies of V
100
90
Phase Angle (degrees)
80
70
60
Experimental Data
50
Theoretical Data
40
30
20
10
0
100
1000
10000
100000
Frequency (Hz)
Part B
v0/V ration for Different Frequencies of V
1.2
1
v0/V
0.8
0.6
Experimental Data
0.4
0.2
0
1000
10000
100000
Frequency (Hz)
1000000
Phase Angles of v0 for Different Frequencies of V
0
1000
-10
10000
100000
Phase Angle (degrees)
-20
-30
-40
Experimental Data
Theoretical Data
-50
-60
-70
-80
-90
Frequency (Hz)
● Conclusion
This lab was instrumental in showing how different frequencies affect RC and RL
circuits. By graphing the results measured, it was clearly shown how the voltage rations
and phase angles relate to the frequency of the input voltage. Computing the theoretical
results proved difficult so it was not possible to see all the relationships between
theoretical and experimental results.