- Briefly explain linear and non-linear systems.
2. Draw the V-I characteristics of practical voltage and current sources. Also, obtain terminal voltage and current relationship for the above sources.
3. Derive the condition for maximum power transfer from a DC source to the resistive load.
4. Find the loop current in the given figure. Also, find the power delivered by 5A current source.
5. Discuss, why complex power is calculated using V I ? Draw the power triangle for both lagging and leading power factors.
6. What is series resonance ? Draw the phasor diagram for series RLC circuit. Also, draw the impedance for the same.
7. Evaluate, the current through each branch and voltages ( Vab, and Vca) in the circuit shown below. Also, draw the phasor diagram by indicating various voltages, currents and their corresponding angles.
8. Derive a mathematical expression for power consumed by a star connected 3-ph load using two wattmeter method. Also, describe the power factor calculation for two wattmeter method.
9. A Y-connected balanced 3-ph generator with an internal impedance of 0.4 + j0.3 Ω per phase is connected to Y-connected balanced load of 24 +j19 Ω per phase. The line joining the generator and the load has impedance of 0.6+j0.7 Ω per phase. Assuming a phase sequence of ABC for the source voltages and that Van = 120 L0° V. Evaluate, supplied wattage, source power factor (pf), line losses (W), load pf, and total power consumed by the 3-ph load.
10. Describe various losses occurs in magnetic circuits. Also, draw the hysteresis (B-H) loop and obtain the mathematical expression for hysteresis losses.
11. The magnetic circuit of the figure shown below has dimensions: A = 4×4 cm , lg = 0.06 cm, lc = 40 cm; N= 600 turns. Assume the value of µ r =6000 for iron. Find the exciting current for Bc = 1.2 T and the corresponding flux and flux linkages.
12. Classify various voltage and current sources.
13. Obtain the relation between the peak and RMS value for a sinusoidal waveform.
14. Draw, impedance triangle, admittance triangle, voltage triangle, and current triangle.
15. Give an analogy table between electrical and magnetic circuit quantities.
16. What do you understand by the accuracy, precision and resolution? Calculate the maximum percentage error in the sum of two voltage measurements when V1 = 20 V± 3% and V2 = 30 V + 2%
17. Demonstrate the application of source transformation by simplifying the given network (shown below) into an equivalent network with a voltage source and series resistance between terminals A and B,
18. Determine currents i1, i2 and i3 for the circuit given below:
19. Obtain the equivalent resistance between terminal A and B.
20. Find the load resistance ( Rxy ) for maximum power transfer between terminals X and Y and also evaluate the power transferred.
21. For the network shown below, the table provides the voltage response across an element ( VR ) along with the corresponding input voltage ( VS ) and input current ( IS ) for several observations. Based on the given data, determine the applied voltage ( VS ) for the 3rd observation.
| Observation No. | VS (V) | IS (A) | VR (V) |
|---|---|---|---|
| 1 | 10 | 2 | 10 |
| 2 | 2 | 5 | 6 |
| 3 | ? | 1.15 | 20 |
22. Derive the admittance and current triangles for a parallel RLC circuit and discuss all possible cases. What happens when the inductive and capacitive susceptance are equal ?