Question 1
Network TheoryTransient Analysis
The time constant of a first-order RL circuit is?
Correct Answer: A. L/R
Explanation: For a series RL first-order circuit, tau = L/R seconds.
Reference: Standard network theory: transient analysis
Transient Analysis MCQs
Practice Transient Analysis MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.
Question 2
Network TheoryTransient Analysis
A 2 H inductor in series with a 10 ohm resistance has an RL time constant of?
Correct Answer: B. 0.2 s
Explanation: tau = L/R = 2/10 = 0.2 s.
Reference: Standard network theory: transient analysis
Question 3
Network TheoryTransient Analysis
In DC steady state after a long time, an ideal capacitor behaves as a?
Correct Answer: B. Open circuit
Explanation: For constant DC voltage, capacitor current i = C dv/dt becomes zero, so an ideal capacitor behaves as an open circuit in steady state.
Reference: Standard network theory: transient analysis
Question 4
Network TheoryTransient Analysis
The time constant of a first-order RC circuit is?
Correct Answer: B. RC
Explanation: The RC time constant is tau = RC seconds.
Reference: Standard network theory: transient analysis
Question 5
Network TheoryTransient Analysis
A 10 kOhm resistor and 10 microfarad capacitor form an RC circuit. Its time constant is?
Correct Answer: B. 0.1 s
Explanation: tau = RC = 10000 × 10×10^-6 = 0.1 s.
Reference: Standard network theory: transient analysis
Question 6
Network TheoryTransient Analysis
Immediately after a switching operation, which quantity of an ideal capacitor cannot change instantaneously?
Correct Answer: B. Voltage
Explanation: Capacitor voltage cannot change instantaneously because an instantaneous finite voltage change would require an impulse or unbounded current according to i = C dv/dt.
Reference: Standard network theory: transient analysis
Question 7
Network TheoryTransient Analysis
Immediately after a switching operation, which quantity of an ideal inductor cannot change instantaneously?
Correct Answer: B. Current
Explanation: Inductor current cannot change instantaneously because v = L di/dt; an instantaneous finite current change would require an impulse or unbounded voltage.
Reference: Standard network theory: transient analysis
Question 8
Network TheoryTransient Analysis
An initially uncharged capacitor is connected through a resistor to a DC source V. After one time constant, its voltage is approximately?
Correct Answer: C. 0.632V
Explanation: For RC charging, vc(t)=V(1-e^(-t/tau)). At t=tau, vc≈V(1-e^-1)=0.632V.
Reference: Standard network theory: transient analysis
Question 9
Network TheoryTransient Analysis
A charged capacitor discharges through a resistor. After one time constant, its voltage is approximately what fraction of its initial value?
Correct Answer: A. 0.368
Explanation: For natural RC discharge, vc(t)=V0e^(-t/tau). At t=tau, vc≈0.368V0.
Reference: Standard network theory: transient analysis
Question 10
Network TheoryTransient Analysis
A series RL circuit with R = 20 ohm and L = 4 H is connected to a DC source. Its time constant is?
Correct Answer: B. 0.2 s
Explanation: For a series RL circuit, tau=L/R=4/20=0.2 s.
Reference: Standard network theory: transient analysis
Question 11
Network TheoryTransient Analysis
A first-order circuit is generally considered very close to its final steady-state value after approximately?
Correct Answer: C. Five time constants
Explanation: After five time constants, a first-order response has completed more than 99% of its total transition and is commonly treated as essentially settled.
Reference: Standard network theory: transient analysis
Question 12
Network TheoryTransient Analysis
A capacitor voltage just before switching is 12 V. If no impulsive current is applied at the switching instant, its voltage immediately after switching is?
Correct Answer: C. 12 V
Explanation: Capacitor voltage cannot change instantaneously without an impulse current, so vC(0+)=vC(0-)=12 V.
Reference: Standard network theory: capacitor continuity
Question 13
Network TheoryTransient Analysis
An inductor carries 3 A just before switching. If no impulsive voltage is applied, its current immediately after switching is?
Correct Answer: C. 3 A
Explanation: Inductor current is continuous in the absence of an impulse voltage, hence iL(0+)=iL(0-)=3 A.
Reference: Standard network theory: inductor continuity
Question 14
Network TheoryTransient Analysis
A series RL circuit has L=2 H and R=10 ohm. Its time constant is?
Correct Answer: B. 0.2 s
Explanation: For an RL circuit, tau=L/R=2/10=0.2 s.
Reference: Standard network theory: RL time constant numerical
Question 15
Network TheoryTransient Analysis
For a source-free RC circuit with R=20 kOhm and C=5 microfarad, the time constant is?
Correct Answer: C. 100 ms
Explanation: tau=RC=20000×5e-6=0.1 s=100 ms.
Reference: Standard network theory: RC time constant numerical
Question 16
Network TheoryTransient Analysis
In a first-order circuit, after approximately five time constants the transient term has fallen to about?
Correct Answer: D. 0.67%
Explanation: The natural term is e^(-t/tau). At t=5tau, e^-5≈0.0067, or about 0.67% of its initial value.
Reference: Standard network theory: settling of first-order response
Question 17
Network TheoryTransient Analysis
For a DC step V applied to an initially uncharged series RC circuit, the capacitor voltage is?
Correct Answer: B. V[1-e^(-t/RC)]
Explanation: The charging response starts at zero and approaches V exponentially: vC(t)=V[1-e^(-t/RC)].
Reference: Standard network theory: RC step response
Question 18
Network TheoryTransient Analysis
A 10 V DC step is applied to an initially uncharged RC circuit. After one time constant, the capacitor voltage is closest to?
Correct Answer: C. 6.32 V
Explanation: At t=tau, vC=V(1-e^-1)≈0.632V=6.32 V.
Reference: Standard network theory: RC charging numerical
Question 19
Network TheoryTransient Analysis
For a DC step V applied to a series RL circuit with zero initial current, the current approaches its final value according to?
Correct Answer: A. (V/R)[1-e^(-tR/L)]
Explanation: The RL step current rises from zero to V/R with time constant L/R: i(t)=(V/R)[1-e^(-tR/L)].
Reference: Standard network theory: RL step response
Question 20
Network TheoryTransient Analysis
The natural response of a linear circuit is produced by?
Correct Answer: A. Stored energy and initial conditions with independent sources set to zero
Explanation: The natural or zero-input response is due to energy initially stored in capacitors and inductors after independent sources are set to zero.
Reference: Standard network theory: natural response
Question 21
Network TheoryTransient Analysis
The zero-state response of a linear circuit is the response when?
Correct Answer: B. Initial conditions are zero and external sources act
Explanation: Zero-state response is caused by external excitation with all independent initial energy-storage conditions set to zero.
Reference: Standard network theory: zero-state response
Question 22
Network TheoryTransient Analysis
The complete response of a linear circuit can be expressed as?
Correct Answer: A. Natural response plus forced response
Explanation: A linear circuit's complete response is commonly decomposed into natural (transient) and forced components.
Reference: Standard network theory: complete response
Question 23
Network TheoryTransient Analysis
For a stable first-order circuit excited by a constant DC source, the natural-response component as t approaches infinity?
Correct Answer: B. Approaches zero
Explanation: A stable first-order natural term has the form Ke^(-t/tau), which decays to zero as time increases.
Reference: Standard network theory: natural response decay
Question 24
Network TheoryTransient Analysis
A first-order circuit has time constant 50 ms. After 150 ms, its natural-response magnitude is approximately what percentage of its initial value?
Correct Answer: C. 5.0%
Explanation: 150 ms equals 3 time constants. e^-3≈0.0498, so about 5% remains.
Reference: Standard network theory: exponential decay numerical