1. Chapter 15 – Series & Parallel ac Circuits Lecture19 - 21 (Tutorial) by Moeen Ghiyas 14/08/2015 1

2. Chapter 15 – Series & Parallel ac Circuits

3. (Series & Parallel ac Circuits) Solution to Related Problems 14/08/2015 3

4. # 1e. Express the impedance of fig. in both polar and rectangular forms. Solution. 14/08/2015 4

5. # 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 14/08/2015 5

6. # 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 14/08/2015 6 5 Ω

7. # 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 14/08/2015 7

8. # 7.For the circuit of Fig: a) Find the total impedance Z T in polar form. b) Draw the impedance diagram. c) Find the current I and the voltages V R and V L in phasor form. d) Draw the phasor diagram of the voltages E, V R, and V L, 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. 14/08/2015 8

9. # 7.For the circuit of Fig: a) Find the total impedance Z T in polar form. b) Draw the impedance diagram. Solution (a) (b) Impedance diagram as on white board 14/08/2015 9

10. # 7.For the circuit of Fig: c) Find the current I and the voltages V R and V L in phasor form. d) Draw phasor diagram. e) Verify result through KVL. Solution Self exercise for phasor diagram and KVL verification 14/08/2015 10

11. # 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) 14/08/2015 11

12. # 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 board 14/08/2015 12

13. # 13. Using the DMM current reading and the oscilloscope measurement: (a) Determine the inductance L Solution. 14/08/2015 13

14. # 13 (b) Find the resistance R. Solution. 14/08/2015 14

15. # 30. For the circuit of Fig. : a. Find the total admittance Y T. b. Draw the admittance diagram. c. Find the value of C in microfarads and L in henries. d. Find the voltage E and currents I R, I L, and I C in phasor form. e. Draw the phasor diagram of the currents I s, I R, I L, and I C, 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. 14/08/2015 15

16. # 30. For the circuit of fig : a. Find total admittance. b. Draw admittance diagram. Solution: Admittance diagram as shown 14/08/2015 16

17. # 30. For the circuit of fig : c. Find the value of C and L. Solution: 14/08/2015 17

18. # 30. For the circuit of fig : e. Draw the phasor diagram d. Find the voltage E and currents I R, I L, and I C in phasor form. Solution: 14/08/2015 18 Phasor diagram as shown

19. # 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:

20. # 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

21. (Series & Parallel ac Circuits) Solution to Related Problems

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