577 + Interview Questions in Networks Analysis and Synthesis in Electronics and Communication Engineering Page 12 InterviewSolution

551.	A capacitor stores 0.15C at 5 V. Its capacitance is
Answer» Q = CV or 0.15 = C(5) or C = 0.03 F.

Discussion

552.	A 0.5 μF capacitor is connected across a 10 V battery. After a long time, the circuit current and voltage across capacitor will be
Answer» When the capacitor is fully charged, i = 0 and voltage across capacitor is equal to battery voltage.

Discussion

553.	For node 1 in figure, KCL equation is
Answer» i(t) is the incoming current. The currents leaving node 1 are

Discussion

554.	In the circuit of figure, the switch is closed at = 0. At = 0 the current through C is
Answer» Capacitor behaves as a short-circuit at t = 0.

Discussion

555.	A series RL circuit has . If a voltage 4 sin + 4 is applied, the steady state current will be
Answer» R = 4 &ohm;, L = 1 H, ω = 4 rad/sec, XL = 4 &ohm;

Discussion

556.	A cable has an insulation resistance of 10 ohms. If the length is doubled, the insulation resistance will be
Answer» Insulation resistance of cable is inversely proportional to length.

Discussion

557.	In the figure shown, A, A, A are identical Ammeters. If A and A read 5 and 13 A respectively, reading of A will be
Answer» A2 = 132 - 25 12 A.

Discussion

558.	The synthesis of minimum function was suggested by
Answer» The procedure is called Brune's synthesis.

Discussion

559.	The electrical energy required to heat a bucket of water to a certain temperature is 2 kWh. If heat losses, are 25%, the energy input is
Answer» Since 25% of input is lost, 0.75 Input = 2 or input =

Discussion

560.	The circuit in figure will act as ideal current source with respect to terminals A and B when frequency is
Answer» When ω = 4 rad/sec ωL and are equal.

Discussion

561.	The current rating of a cable depends on
Answer» Current rating depends only on area of cross-section and hence diameter.

Discussion

562.	In an ac circuit, the maximum and minimum values of power factor can be
Answer» Power factor is maximum and equal to 1 for purely resistive load. Power factor is minimum and equal to zero for purely reactive load.

Discussion

563.	An infinite ladder is constructed with 1 &ohm; and 2 &ohm; resistors shown below.
Answer» R = 1 + (2 \|\| R) R = 2 .

Discussion

564.	In the circuit of figure the voltage across capacitor when switch is closed at = ∞ is
Answer» Voltage across capacitor = voltage across 3&ohm; resistance =

Discussion

565.	C = (2) (energy)/V
Answer»

Discussion

566.	A 3 phase balanced supply feeds 3 phase unbalanced load. Power supplied to the load can be measured by using Which of the above statements is correct?
Answer» A minimum of 2 wattmeters is required to measure 3 phase power. Of course power can be measured by putting one wattmeter in each phase.

Discussion

567.	In the series circuit shown in figure, for series resonance, the value of the coupling coefficient, K will be
Answer» Mutual inductance wm = ωk L1L2 m = k. 2. 8j2 = 4k. j Z = 20 - j10 + j2 + j6 + 2.4kj - 2j + 8kj = 0 at resonance -2 = -8k k = 1/4 0.25 .

Discussion

568.	The degree of the nodes 1, 2, 3, 4 is
Answer» Degree of node is the no.of branch incident to it.

Discussion

569.	In an RC series circuit R = 100 &ohm; and X = 10 &ohm;. In this circuit
Answer» In RC circuit the current leads the voltage.

Discussion

570.	The impedance of an RC series circuit is 12 &ohm; at = 50 Hz. At = 200 Hz, the impedance will be
Answer» Z = R2 + XC2. When f is made four times, XC becomes one-fourth but R remains the same.

Discussion

571.	A current is flowing through a conductor with non-uniform area of cross-section. Then
Answer» Current density = current/area of cross-section. Same current throughout the conductor. Since, area of cross-section is non-uniform, current density will be different at different cross-sections.

Discussion

572.	The time constant of the circuit in figure shown.
Answer» Time constant Req.C when V is shorted and R is seen from C then Req = R \|\| R = R/2 .

Discussion

573.	In the circuit shown in given figure, the values of i(0) and I(∞), will be respectively
Answer» I(t) = 6 e-t - 3 e-0.5t at t = 0, I(0) = 3A at t = ∞, I(∞) = 0.

Discussion

574.	As compared to the number of network elements in Brune synthesis, the number of network elements Bott-and Duffin in realization is
Answer» To avoid mutually coupled inductors, more elements are needed.

Discussion

575.	A two branch parallel circuit has a 20 &ohm; resistance and 1 H inductance in one branch and a 100 μF capacitor in the second branch. It is fed from 100 V ac supply, at resonance, the input impedance of the circuit is
Answer» At parallel resonance circuit impedance = .

Discussion

576.	The impedance matrices of two, two-port network are given by and . If these two networks are connected in series, the impedance matrix of the resulting two-port network will be
Answer» Impedance matrices will be added.

Discussion

577.	RMS value of () = 10[1 + sin (- )] is
Answer» .

Discussion

Explore topic-wise InterviewSolutions in .

A capacitor stores 0.15C at 5 V. Its capacitance is

A 0.5 μF capacitor is connected across a 10 V battery. After a long time, the circuit current and voltage across capacitor will be

For node 1 in figure, KCL equation is

In the circuit of figure, the switch is closed at = 0. At = 0 the current through C is

A series RL circuit has . If a voltage 4 sin + 4 is applied, the steady state current will be

A cable has an insulation resistance of 10 ohms. If the length is doubled, the insulation resistance will be

In the figure shown, A, A, A are identical Ammeters. If A and A read 5 and 13 A respectively, reading of A will be

The synthesis of minimum function was suggested by

The electrical energy required to heat a bucket of water to a certain temperature is 2 kWh. If heat losses, are 25%, the energy input is

The circuit in figure will act as ideal current source with respect to terminals A and B when frequency is

The current rating of a cable depends on

In an ac circuit, the maximum and minimum values of power factor can be

An infinite ladder is constructed with 1 &ohm; and 2 &ohm; resistors shown below.

In the circuit of figure the voltage across capacitor when switch is closed at = ∞ is

C = (2) (energy)/V

A 3 phase balanced supply feeds 3 phase unbalanced load. Power supplied to the load can be measured by using Which of the above statements is correct?

In the series circuit shown in figure, for series resonance, the value of the coupling coefficient, K will be

The degree of the nodes 1, 2, 3, 4 is

In an RC series circuit R = 100 &ohm; and X = 10 &ohm;. In this circuit

The impedance of an RC series circuit is 12 &ohm; at = 50 Hz. At = 200 Hz, the impedance will be

A current is flowing through a conductor with non-uniform area of cross-section. Then

The time constant of the circuit in figure shown.

In the circuit shown in given figure, the values of i(0) and I(∞), will be respectively

As compared to the number of network elements in Brune synthesis, the number of network elements Bott-and Duffin in realization is

A two branch parallel circuit has a 20 &ohm; resistance and 1 H inductance in one branch and a 100 μF capacitor in the second branch. It is fed from 100 V ac supply, at resonance, the input impedance of the circuit is

The impedance matrices of two, two-port network are given by and . If these two networks are connected in series, the impedance matrix of the resulting two-port network will be

RMS value of () = 10[1 + sin (- )] is