# Advanced Problems on Network Theory – 1 MCQ’s

This set of Network Theory Multiple Choice Questions & Answers (MCQs) focuses on “Advanced Problems on Network Theory – 1″.

1. A capacitor, used for power factor correction in a single phase circuit decreases which of the following?

a) Power factor

b) Line current

c) Both Line current and Power factor

d) Neither Line current nor Power factor

2. D is the distance between the plates of a parallel plate capacitor. The dielectric constants are ∈_{1} and ∈_{2} respectively. The total capacitance is proportional to ____________

a) ∈1∈2∈1+∈2

b) ∈_{1} – ∈_{2}

c) ∈1∈2

d) ∈_{1} ∈_{2}

3. Branch current and loop current relation is expressed in matrix form shown below, where Ij represents branch current and Ik represents loop current.

[I_{1}; I_{2}; I_{3}; I_{4}; I_{5}; I_{6}; I_{7}; I_{8}] = [0 0 1 0; -1 -1 -1 0; 0 1 0 0; 1 0 0 0; 0 0 -1 -1; 1 1 0 -1; 1 0 0 0; 0 0 0 1] [I_{1}; I_{2}; I_{3}; I_{4}] The rank of the incidence matrix is?

a) 4

b) 5

c) 6

d) 8

4. A two branch circuit has a coil of resistance R_{1}, inductance L_{1} in one branch and capacitance C_{2} in the second branch. If R is increased, the dynamic resistance is going to ___________

a) Increase

b) Decrease

c) Remains constant

d) May increase or decrease

5. For the two circuits shown below, the relation between I_{A} and I_{B} is ________

a) I_{B} = I_{A} + 6

b) I_{B} = I_{A} + 2

c) I_{B} = 1.5I_{A}

d) I_{B} = I_{A}

6. An AC source of RMS voltage 20 V with internal impedance Z_{S} = (1+2j) Ω feeds a load of impedance Z_{L} = (7+4j) Ω in the circuit given below. The reactive power is _________

a) 8 VAR

b) 16 VAR

c) 28 VAR

d) 32 VAR

7. A 1 μF capacitor is connected to 12 V batteries. The energy stored in the capacitor is _____________

a) 12 x 10^{-6} J

b) 24 x 10^{-6} J

c) 60 x 10^{-6} J

d) 72 x 10^{-6} J

8. For the circuit given below, the current I in the circuit is ________

a) –j1 A

b) J1 A

c) Zero

d) 20 A

9. In the circuit given below, R_{I} = 1 MΩ, R_{O} = 10 Ω, A = 10^{6} and V_{I} = 1μV. Then the output voltage, input impedance and output impedance respectively are _________

a) 1 V, ∞ and 10 Ω

b) 1 V, 0 and 10 Ω

c) 1V, 0 and ∞

d) 10 V, ∞ and 10 Ω

10. For making a capacitor, the dielectric should have __________

a) High relative permittivity

b) Low relative permittivity

c) Relative permittivity = 1

d) Relative permittivity neither too high nor too low

11. If A = 3 + j1, then A^{4} is equal to __________

a) 3.16 ∠18.4°

b) 100 ∠73.72°

c) 100 ∠18.4°

d) 3.16 ∠73.22°

12. If operator ‘a’ = 1 ∠120°. Then (1 – a) is equal to ____________

a) 3–√

b) 3–√∠-30°

c) 3–√∠30°

d) 3–√∠60°

13. In the figures given below, Value of R_{A}, R_{B} and R_{C} are 20 Ω, 10 Ω and 10 Ω respectively. The resistances R_{1}, R_{2} and R_{3} in Ω are ________

a) 2.5, 5 and 5

b) 5, 2.5 and 5

c) 5, 5 and 2.5

d) 2.5, 5 and 2.5

14. In the circuit shown below, the voltage V will be __________

a) – 3V

b) Zero

c) 3 V

d) 5 V

15. The resistance of a thermistor decreases with increases in __________

a) temperature

b) circuit

c) light control

d) sensors