User's Manual

55
012-05892A AC/DC Electronics Laboratory
®
Data Table
Freq(Hz) V
o
V
R
Freq(Hz) V
o
V
R
10 90
20 100
30 110
40 120
50 130
60 140
70 150
80
Item Value
Resonant frequency Hz
Resonant angular frequency Hz
Inductance mH
Capacitance µF
Theoretical resonant angular frequency Hz
Questions
➀ How does your measured value for resonant angular frequency compare to the theoretical value
for resonant angular frequency?
Remember,
Percent difference =
theoretical − actual
theoretical
x100%
➁ Is the plot of current (V
R
/V
o
) versus frequency symmetrical about the resonant frequency?
Explain.
➂ At resonance, the reactances of the inductor and the capacitor cancel each other so that the
impedance (Z) is equal to just the resistance (R). Calculate the resistance of the circuit by using
the amplitude of the current at resonance in the equation
R
=
V
I
(where V is the amplitude of
the applied voltage). Is this resistance equal to 10 Ω? Why not?