Each question carries 2 marks.

Negative marking: 2/3 mark

Total Questions: 10

Time: 20 min.

Q1. For the circuit given in figure below the power delivered by the 2-volt source is given by

(a) 4 W

(b) -4 W

(c) 2 W

(d) -2 W

Q2. If the torque/weight ratio of an instrument is low, then it can be concluded that

(a) The meter will have a uniform scale

(b) The meter will have the non-uniform scale

(c) The sensitivity of the meter will be high

(d) The sensitivity of the meter will be low

Q3. The Y_bus matrix of a 100-bus interconnected system is 80% sparse. Then, the number of transmission lines in the system must be

(a) 1500

(b) 1900

(c) 3000

(d) 950

Q4. The bus admittance matrix of a power system is given by

The impedance of line between bus 2 and 3 will be equal to:

(a) -j0.5

(b) j0.1

(c) j0.2

(d) -j0.2

Q5. There are N resistances, each are connected in parallel having value R with the equivalent resistance of X. What will be the total resistance when these N resistances are connected in series?

(a) NX

(b) RNX

(c) X/N

(d) N2X

Q6. A chopper circuit fed from an input voltage of 20 V DC, delivers a load power of 16 W. for a chopper efficiency of 0.8, the input current is

(a) 0.8 A

(b) 0.64 A

(c) 1 A

(d) 1.25 A

Q7. The Fourier series of a real periodic function has only

(P) cosine terms if it is even

(Q) sine terms if it is even

(R) cosine terms if it is odd

(S) sine terms if it is odd

Which of the above statements are correct?

(a) P and S

(b) P and R

(c) Q and S

(d) Q and R

Q8. If, in a DC machine, the ratio of constant losses to armature resistance is 3, then at maximum efficiency, the magnitude of current flowing will be:

(a) 3 A

(b) 1.732 A

(c) 9 A

(d) 6.667 A

Q9. Which of the following features are offered by a bipolar junction transistor amplifier in Darlington connection?

1. High current gain

2. High voltage gain

3. High input impedance

Select the correct answer using the code given below:

(a) 1 and 2 only

(b) 2 and 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

Q10. The currents in a 3-phase unbalanced system are:

(I_R ) =(12+j 6)A ;

(I_Y ) =(12-j 12)A ;

(I_B ) =(-15+j 10)A

The phase sequence is RYB. The zero-phase sequence component in R-phase is

(a) (1.5 + j 2.3) A

(b) (3 + j 1.33) A

(c) (2.8 + j 6.7) A

(d) (1.5 + j 0.15) A

SOLUTIONS