Chapter 15 – Series & Parallel ac Circuits

Lecture19 - 21 (Tutorial)

by Moeen Ghiyas

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Chapter 15 – Series & Parallel ac Circuits

(Series & Parallel ac Circuits)

Solution to Related Problems

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# 1e. Express the impedance of fig. in both polar and

rectangular forms.

Solution.

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# 2c. Find the current i for the elements of fig. using

complex algebra. Sketch the waveforms for v and i on the

same set of axes.

Solution.

. Sketch as on white board

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# 5a. Calculate the total impedance of the circuit in

rectangular and polar forms, and draw the impedance

diagram.

Solution.

Impedance diagram as on white board

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5 Ω

# 6a. Find the type and impedance in ohms of the series

circuit elements that must be in the closed container of Fig

Solution.

Draw resistance and capacitor in series in the box

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# 7. For the circuit of Fig:

a) Find the total impedance ZT in polar form.

b) Draw the impedance diagram.

c) Find the current I and the voltages VR and VL in phasor form.

d) Draw the phasor diagram of the voltages E, VR , and VL , and the current I.

e) Verify Kirchhoff’s voltage law around the closed loop.

f) Find the average power delivered to the circuit.

g) Find the power factor of the circuit, and indicate whether it is leading or

lagging.

h) Find the sinusoidal expressions for the voltages and current if the frequency is

60 Hz.

i) Plot the waveforms for the voltages and current on the same set of axes. 19/04/23 8

# 7. For the circuit of Fig:

a) Find the total impedance ZT in polar form.

b) Draw the impedance diagram.

Solution

(a)

(b) Impedance diagram as on white board

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# 7. For the circuit of Fig:

c) Find the current I and the voltages VR and VL in phasor form.

d) Draw phasor diagram.

e) Verify result through KVL.

Solution

Self exercise for phasor diagram and KVL verification

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# 7. For the circuit of Fig:

f) Find the average power delivered to the circuit.

g) Find the power factor of the circuit, and indicate whether it is

leading or lagging.

Solution

(f)

(g)19/04/23 11

# 7. For the circuit of Fig:

h) Find the sinusoidal expressions for the voltages and current if the

frequency is 60 Hz.

i) Plot the waveforms for the voltages and current on the same set of

axes.

Solution

(h)

(i) Plot as on white board19/04/23 12

# 13. Using the DMM current reading and the oscilloscope

measurement: (a) Determine the inductance L

Solution.

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# 13 (b) Find the resistance R.

Solution.

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# 30. For the circuit of Fig. :

a. Find the total admittance YT.

b. Draw the admittance diagram.

c. Find the value of C in microfarads and L in henries.

d. Find the voltage E and currents IR, IL, and IC in phasor form.

e. Draw the phasor diagram of the currents Is, IR, IL, and IC, and the voltage E.

f. Verify Kirchhoff’s current law at one node.

g. Find the average power delivered to the circuit.

h. Find the power factor of the circuit, and indicate whether it is leading or

lagging.

i. Find the sinusoidal expressions for the currents and voltage.

j. Plot the waveforms for the currents and voltage on the same set of axes.19/04/23 15

# 30. For the circuit of fig :

a. Find total admittance.

b. Draw admittance diagram.

Solution:

Admittance diagram as shown

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# 30. For the circuit of fig :

c. Find the value of C and L.

Solution:

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# 30. For the circuit of fig :

e. Draw the phasor diagram

d. Find the voltage E and currents IR, IL, and IC in phasor form.

Solution:

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Phasor diagramas shown

# 30. For the circuit of fig :

f. Verify Kirchhoff’s current law.

g. Find the average power delivered to the circuit.

h. Find the power factor of the circuit

Solution:

# 30. For the circuit of fig :

i. Find the sinusoidal expressions.

j. Plot the waveforms for the currents and voltage on the same set of axes.

Solution:

Plot the waveform yourself as an exercise

(Series & Parallel ac Circuits)

Solution to Related Problems

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