SKR Engineering College 2007 B.E Electrical and Electronics Engineering EE 1X01 – ELECTRIC CIRCUIT ANALYSIS - Question Paper

SKR ENGINEERING COLLEGE
DEPARTMENT OF ELECTRICAL& ELECTRONICS ENGG
1-YEAR - EEE
EE 1X01 – ELECTRIC CIRCUIT ANALYSIS
MODEL examination

DATE: 13.03.07 MAXIMUM MARKS: 100
TIME DURATION: three Hrs
PART –A (10 x two =20)
1. Define an ideal current source.
2. How a star connected network is converted into a delta network?
3. Define poles and zeros
4. Draw the transient response of RL circuit to step input voltage
5. What are half power frequencies?
6. Define bandwidth
7. State Thevenin’s theorem
8. Give a few applications of maximum power transfer theorem
9. What is the maximum possible mutual inductance of 2 inductively coupled coil with self-inductance L1 =15mH, L2 =50mH?
10. Write an expression for power factor in a balanced 3 phase circuit.

PART –B
(5 x 16=80)
(Answer all the questions)

11. (a) (i) explain V-I relationship of circuit elements (4)
(ii) compute the current through 6-ohm resistance of the provided network by
Application of kirchoff’s laws (6)





(iii) obtain the value of R and current through it in the circuit of fig (6)





[OR]
(b) (i) describe and discuss kirchoff’s laws(6)
(ii) What values must R1 and R2 have when I1 =4A and I2 = 6A both charging
in the circuit fig provided beneath. (10)










12 (a) (i) Derive the expression for step response of RLC series circuit for critical damping
Condition. (16)
[OR]
(b) (i) Consider RLC series circuit of the provided fig R=2 O, L=0.5 H and C=0.1F.The
Circuit is initially relaxed. When the switch is closed at t=0. compute the transient
Current and voltage across the capacitor. (10)
(ii) Steady state condition exists in the circuit of the provided fig. The switch is opened
At t=0. Determine the expression for I (t), t >0. (6)

13 (a) (i) obtain avg. power, apparent power, reactive power and power factor for the fig provided beneath. (8)






(ii) for provided circuit obtain impedance,current,angle, voltage drop across resistor, inductor and capacitor. (8)







[OR]
(b) (i) obtain the value of L at which the circuit resonance at a frequency at of 1000 Hz in the circuit shown in fig (8)







(ii) Derive the expression for the resonance frequency for the figure shown in fig. (8)








14 (a) (i) using mesh analysis ,find current through four ohm resistor.(8)





(ii) For the circuit shown, determine Norton’s equivalent circuit ranging from the output
terminals AB. (8)





[OR]

(b) (i) Solve the voltage VI and V2 using Nodal method. Let v=100volts.(8)







(ii) Using superposition theorem obtain the current in the 10 ohm resistor for the
Network shown beneath. (8)





15 a) (i) Briefly discuss the following: (8)
· Mutual inductance
· Dot conversion
(ii) The power input to a load was measured by two-wattmeter method. The readings were 800W and 400W, the later readings having been found by reversing the potential coil connections. obtain power and power factor of load. (8)

[OR]
(b) (i) a 3 phase balanced delta connected load of (4+j8) ohm is connected across a 400V, three phase balanced supply.Determine the phase currents and line currents. presume the RYB sequence.Also compute the power drawn by the load. (10)

(ii) 2 watt meters are used to measure power in a three-phase load. The wattmeter readings are 400W and –35W. compute total active power, power factor and reactive power. (6)

Earning:   Approval pending.