# GATE Questions & Answers of Transient Response of DC and AC Networks

## What is the Weightage of Transient Response of DC and AC Networks in GATE Exam?

Total 18 Questions have been asked from Transient Response of DC and AC Networks topic of Electric Circuits subject in previous GATE papers. Average marks 1.61.

A DC voltage source is connected to a series L-C circuit by turning on the switch S at time $t=0$ as shown in the figure. Assume $i(0)=0,v(0)=0$ . Which one of the following circular loci represents the plot of $i(t)$ versus $v(t)\;?$

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The switch in the figure below was closed for a long time. It is opened at t = 0. The current in the inductor of 2 H for , is

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The initial charge in the 1 F capacitor present in the circuit shown is zero. The energy in joules transferred from the DC source until steady state condition is reached equals_________.(Give the answer up to one decimal place.)

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In the circuit shown, switch S2 has been closed for a long time. At time $t=0$ switch S1 is closed. At $t=0^+$, the rate of change of current through the inductor, in amperes per second, is _____.

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A resistance and a coil are connected in series and supplied from a single phase, 100 V, 50 Hz ac source as shown in the figure below. The rms values of plausible voltages across the resistance (VR) and coil (VC) respectively, in volts, are

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In the circuit shown below, the initial capacitor voltage is 4 V. Switch $S_1$ is closed at $t=0$. The charge (in $\mu C$) lost by the capacitor from $t=25\;\mu$s to $t=100\;\mu$s is ____________.

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A series RL circuit is excited at t = 0 by closing a switch as shown in the figure. Assuming zero initial conditions, the value of $\frac{{\mathrm{d}}^{2}i}{\mathrm{d}{t}^{2}}$ at t = ${0}^{+}$ is

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A combination of 1 µF capacitor with an initial voltage${\nu }_{c}\left(0\right)=-2\nu$ in series with a 100 O resistor is connected to a 20 mA ideal dc current source by operating both switches at t = 0 s as shown. Which of the following graphs shown in the options approximates the voltage vs across the current source over the next few seconds?

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The switch SW shown in the circuit is kept at position ‘1’ for a long duration. At t = 0+, the switch is moved to position ‘2’. Assuming |Vo2| > |Vo1|, the voltage vc(t) across the capacitor is

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In the following figure, C1 and C2 are ideal capacitors. C1 has been charged to 12 V before the ideal switch S is closed at t = 0. The current i(t) for all t is

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The switch in the circuit has been closed for a long time. It is opened at t = 0. At t = 0+, the current through the 1μF capacitor is

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The L-C circuit shown in the figure has an inductance L = 1mH and a capacitance C= 10μF

The initial current through the inductor is zero, while the initial capacitor voltage is 100 V. The switch is closed at t = 0. The current i through the circuit is:

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The L-C circuit shown in the figure has an inductance L = 1mH and a capacitance C= 10μF

The L-C circuit of Q54 is used to commutate a thyristor, which is initially carrying a current of 5A as shown in the figure below. The values and initial conditions of L and C are the same as in Q54. The switch is closed at t = 0. If the forward drop is negligible, the time taken for the device to turn off is

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In the figure shown, all elements used are ideal. For time t<0, S1 remained closed and S2 open. At t=0, S1 is opened and S2 is closed. If the voltage Vc2 across the capacitor C2 at t=0 is zero, the voltage across the capacitor combination at t=0+ will be

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The time constant for the given circuit will be

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The current  i(t) sketched in the figure flows through a initially uncharged 0.3 nF capacitor.

The charge stored in the capacitor at t = 5 μs, will be

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The current  i(t) sketched in the figure flows through a initially uncharged 0.3 nF capacitor.

The capacitor charged upto 5 ms, as per the current profile given in the figure, is connected across an inductor of 0.6 mH. Then the value of voltage across the capacitor after 1 μs will approximately be

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In the circuit shown in figure. Switch SW1 is initially CLOSED and SW2 is OPEN. The inductor L carries a current of 10 A and the capacitor charged to 10 V with polarities as indicated. SW2 is initially CLOSED at t=0- and SW1 is OPENED at t = 0. The current through C and the voltage across L at t = 0+ is