Question 1
A choke can be electrically modeled as an RL circuit with an ideal inductor in series with a resistor.
TRUE
FALSE
The IIT Madras BS Electrical and Electronic Circuits (Electrical and Electronic Circuits) Quiz 1 paper sat on 26 Oct 2025, in the September 2025 term, set QED2: 22 questions for 35.5 marks in 120 minutes. Every question is below with its answer. Take it as a timed mock test to be marked, or read it through first.
A choke can be electrically modeled as an RL circuit with an ideal inductor in series with a resistor.
TRUE
FALSE
Correct answer
TRUE
Pure resistive networks have a power factor of zero.
TRUE
FALSE
Correct answer
FALSE
TRUE
FALSE
Correct answer
FALSE
TRUE
FALSE
Correct answer
TRUE
Consider a switched capacitor circuit, where the switch abruptly changes from one position (A) to another (B). Assume the transition time is ideally zero. The switching action is best modeled as a step function.
TRUE
FALSE
Correct answer
TRUE
The reactance offered by a capacitor to an alternating current of frequency 50 Hz is 10 Ω. If the frequency is increased to 100 Hz, the reactance becomes
20 Ω
5 Ω
0.5 Ω
0.20 Ω
Correct answer
5 Ω
Consider a series RLC circuit at resonance. Choose the right option.
Statement 1: The current flowing through the circuit is dependent only on the resistance value. Statement 2: The input impedance offered by the circuit is minimum. Statement 3: The voltage across the capacitor can exceed the applied source voltage. Statement 4: The magnitude of the inductive reactance is equal to the capacitive reactance.
Statements 1 and 2 are only true.
Statements 3 and 4 are only true.
Statements 1, 2, and 4 are only true.
All the statements are true.
Correct answer
All the statements are true.
1 V
7 V
5 V
10 V
Correct answer
5 V
2
4
0.02
0.04
Correct answer
2
A load is connected to a network. Across the terminals to which the load is connected, the Thevenin equivalent resistance Rth = 10 Ω and Thevenin equivalent voltage Vth = 20 V. The maximum possible power (in W ) that can be supplied to the load is
5 W
2.5 W
10 W
4 W
Correct answer
10 W
500 VA
866 VA
1000 VA
2000 VA
Correct answer
2000 VA
1 and 2
1 and 4
2 and 3
3 and 4
Correct answer
1 and 4
Based on the above data, answer the given subquestions.
The value of R (in Ω) is _________
Correct answer: 5
Based on the above data, answer the given subquestions.
The value of L ( in H) is _________
Correct answer: 2.5
Based on the above data, answer the given subquestions.
The Thevenin voltage (in V) across A and B is _______
Correct answer: -6
Based on the above data, answer the given subquestions.
The Thevenin resistance (in Ω) between A and B is _________
Correct answer: -12
For an AC circuit, the average power consumed by the circuit is 60 W. The apparent power is 100 VA. The power factor of the circuit is ______
Correct answer: 0.6
The potential difference measured across a coil is 4.5 V when it carries a direct current of 9 A. The same coil, when it carries an alternating current of 9 A at 25 Hz, the potential difference is 24 V. Determine the given subquestions:
The coil resistance in Ω.
Correct answer: 0.5
The potential difference measured across a coil is 4.5 V when it carries a direct current of 9 A. The same coil, when it carries an alternating current of 9 A at 25 Hz, the potential difference is 24 V. Determine the given subquestions:
The value of the choke inductance in mH.
Correct answer: 16.8 (accepted within ±0.2)
The potential difference measured across a coil is 4.5 V when it carries a direct current of 9 A. The same coil, when it carries an alternating current of 9 A at 25 Hz, the potential difference is 24 V. Determine the given subquestions:
Now, if the coil is connected across a 50 V(RMS), 50 Hz supply.
The RMS value of the current (in A) flowing through the coil.
Correct answer: 9.5
The potential difference measured across a coil is 4.5 V when it carries a direct current of 9 A. The same coil, when it carries an alternating current of 9 A at 25 Hz, the potential difference is 24 V. Determine the given subquestions:
Now, if the coil is connected across a 50 V(RMS), 50 Hz supply. The power consumed by the coil (in W)
Correct answer: 45.1 (accepted within ±0.1)
The potential difference measured across a coil is 4.5 V when it carries a direct current of 9 A. The same coil, when it carries an alternating current of 9 A at 25 Hz, the potential difference is 24 V. Determine the given subquestions:
Now, if the coil is connected across a 50 V(RMS), 50 Hz supply.
The power factor of the circuit.
Correct answer: 0.095 (accepted within ±0.005)