1.      State Kirchhoff’s law for electric circuits?
2.      State the VI relationship in inductor and Capacitor?
3.      Define RMS Value?
4.      State Maximum power Transfer Theorem?
5.      Express resonant frequency in terms of half power frequencies?
6.      List the properties of  Ideal transformer?
7.      Calculate the time constant of Rc circuit having R= 1k and c= 1µf
8.      How does an inductor act at t= 0+ & t=?
9.      Draw the circuit diagram to measure 3φ Reactive power using one wattmeter?
10.  How are the wattmeter readings equal in two wattmeter method at UPF? Establish the condition mathematically?
PART-B
11.  (a)Use node Voltage method to find voltage of node m and currents I1, I2 & I3 in the circuit theorem?                                                                                                              (16)
(or)
(b) In the network shown find the current through all the branches?                           (16)
12.  (a) Find the Value of RL. So that max power is delivered to the load Resistance RL. (16)
(or)
(b) For the circuit shown determine the current in (2+j3) by superposition theorem?

13.  (i)Explain the characteristics of series RLC circuit?                                                (6)
(ii) Find the value of   .So that the current and source Emf are in phase. Also find the current at this Frequency?

(or)
(b) (i) Briefly Explain the following
(a) Mutual inductance?
(b) Dot convention?
(ii) Obtain the equivalent inductance when two inductance are corrected in
(a)    Series aiding  b)Series opposing  c)Parallel aiding d) Parallel opposing
14.  For the circuit shown below, Let the transient current when the switch in transferred from position 1 to position 2 at t=0
(or)
b) Derive the expression for step response of RLC series circuit for critical damping condition(16)
15.  (a) (i) Prove that two watt meters are sufficient to measure 3φ power.                    (8)
(ii) A symmetrical 3φ 400 V System supplies a balanced delta connected load. The current in each branch circuit is 20A and phase angle 40º load calculate line current and total power(8)
OR
(b) (i)The power input to a load was measured by two wattmeter method the readings were 800 W and 400 w. the  meter reading having been obtained by reversing the potential coil connections find power and power factor?                                                                                     (8)
(ii) Explain the effect of power factor on wattmeter readings?

Circuit Theory important questions Anna university chennai Reviewed by Rejin Paul on 5:42 AM Rating: 5