Explore topic-wise MCQs in Network Theory.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Network Theory knowledge and support exam preparation. Choose a topic below to get started.

1.

The four arms of an AC bridge network are as follows:Arm AB: unknown impedanceArm BC: standard capacitor C2 of 1000pfArm CD: a non-inductive resistance of R of 100 Ω in parallel to a capacitor of 0.01 μFArm DA: a non-inductive resistance of 1000 ΩThe supply frequency is 50 Hz and connected across terminals B and D. If the bridge is balanced with the above value, determine the value of unknown Impedance.

A. 10 kΩ
B. 100 kΩ
C. 250 kΩ
D. 20 kΩ
Answer» B. 100 kΩ
2.

In the figure below, the values of the resistance R1 and inductance L1 of a coil are to be calculated after the bridge is balanced. The values are _________________

A. 375 Ω and 75 mH
B. 75 Ω and 150 mH
C. 37.5 Ω and 75 mH
D. 75 Ω and 75 mH
Answer» B. 75 Ω and 150 mH
3.

In Maxwell’s capacitance bridge for calculating unknown inductance, the various values at balance are, R1 = 300 Ω, R2 = 700 Ω, R3 = 1500 Ω, C4 = 0.8 μF. The values of R1, L1 and Q factor, if the frequency is 1100 Hz are ____________

A. 240 Ω, 0.12 H, 3.14
B. 140 Ω, 0.168 H, 8.29
C. 140 Ω, 0.12 H, 5.92
D. 240 Ω, 0.36 H, 8.29
Answer» C. 140 Ω, 0.12 H, 5.92
4.

In the Owen’s bridge shown in below figure, Z1 = 200∠60°, Z2 = 400∠-90°, Z3 = 300∠0°, Z4 = 400∠30°. Then,

A. Bridge is balanced with given impedance values
B. Bridge can be balanced, if Z4 = 600∠60°
C. Bridge can be balanced, if Z3 = 400∠0°
D. Bridge cannot be balanced with the given configuration
Answer» E.
5.

In the figure given below, a 220 V 50 Hz supplies a 3-phase balanced source. The pressure Coil (PC) and Current Coil (CC) of a watt-meter are connected to the load as shown. The watt-meter reading is _________

A. Zero
B. 1600 W
C. 242 W
D. 400 W
Answer» D. 400 W
6.

The meter constant of a single-phase, 230 V induction watt-meter is 600 rev/kW-h. The speed of the meter disc for a current of 15 A at 0.8 power factor lagging will be?

A. 30.3 rpm
B. 25.02 rpm
C. 27.6 rpm
D. 33.1 rpm
Answer» D. 33.1 rpm
7.

In the Two wattmeter method of measuring power in a balanced three-phase circuit, one wattmeter shows zero and the other positive maximum. The load power factor is ___________

A. 0
B. 0.5
C. 0.866
D. 1.0
Answer» C. 0.866
8.

A 200/1 Current Transformer (CT) is wound with 400 turns on the secondary on a toroidal core. When it carries a current of 180 A on the primary, the ratio is found to be -0.5%. If the number of secondary turns is reduced by 1, the new ratio error (in %) will be?

A. 0
B. -0.5
C. -1.0
D. -2.0
Answer» D. -2.0
9.

A resistor of 10 kΩ with a tolerance of 5% is connected in parallel with 5 kΩ resistors of 10% tolerance. The tolerance limit is __________

A. 9%
B. 12.4%
C. 8.33%
D. 7.87%
Answer» D. 7.87%
10.

The simultaneous applications of signals x (t) and y (t) to the horizontal and vertical plates respectively, of an oscilloscope, produce a vertical figure of 8 displays. If P and Q are constants and x(t) = P sin (4t + 30), then y(t) is equal to _________

A. Q sin (4t – 30)
B. Q sin (2t + 15)
C. Q sin (8t + 60)
D. Q sin (4t + 30)
Answer» C. Q sin (8t + 60)
11.

The readings of polar type potentiometer areI = 12.4∠27.5°V = 31.5∠38.4°Then, Reactance of the coil will be?

A. 2.51 Ω
B. 2.56 Ω
C. 2.54 Ω
D. 2.59 Ω
Answer» D. 2.59 Ω
12.

The voltage drop across a standard resistor of 0.2 Ω is balanced at 83 cm. The magnitude of the current, if the standard cell emf of 1.53 V is balanced at 42 m is ___________

A. 13.04 A
B. 10 A
C. 14.95 A
D. 12.56 A
Answer» D. 12.56 A
13.

In the Wheatstone bridge shown below, if the resistance in each arm is increased by 0.05%, then the value of Vout will be?

A. 50 mV
B. Zero
C. 5mV
D. 0.1mV
Answer» C. 5mV
14.

An RLC series circuit has a resistance R of 20Ω and a current which lags behind the applied voltage by 45°. If the voltage across the inductor is twice the voltage across the capacitor, the value of inductive resistance is ____________

A. 10 Ω
B. 20 Ω
C. 40 Ω
D. 60 Ω
Answer» D. 60 Ω
15.

If the 3-phase balanced source in the given figure delivers 1500 W at a leading power factor of 0.844, then the value of ZL is approximately __________

A. 90∠32.44°
B. 80∠32.44°
C. 80∠-32.44°
D. 90∠-32.44°
Answer» E.