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The value of the quantity P, where , is equal to

0

1

e

1/e

Divergence of the three-dimensional radial vector field is :

3

1/r

The period of the signal is :

The system represented by the input-output relationship is :

Linear and causal

Linear but not causal

Causal but not linear

Neither linear nor causal

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

0 A

1 A

1.25 A

5 A

The second harmonic component of the periodic waveform given in the figure has an amplitude of

As shown in the below figure, a resistance is connected across a source that has a load line v + i =100 . The current through the resistance is :

25 A

50 A

100 A

200 A

A wattmeter is connected as shown in the below figure. The wattmeter reads

Zero always

Total power consumed by

Power consumed by

An ammeter has a current range of 0 – 5 A, and its internal resistance is . In order to change the range to 0 – 25 A, we need to add a resistance of

As shown in the figure, a negative feedback system has an amplifier of gain 100 with 10% tolerance in the forward path, and an attenuator of value 9/100 in the feedback path. The overall system gain is approximately :

10 1 %

10 2 %

10 5 %

10 10 %

For the system 2 / (s +1) , the approximate time taken for a step response to reach 98% of its final value is :

1s

2s

4s

8s

If the electrical circuit of figure (b) is an equivalent of the coupled tank system of figure (a), then

A, B are resistances and C, D capacitances

A, C are resistances and B, D capacitances

A, B are capacitances and C, D resistances

A, C are capacitances and B, D resistances

A single-phase transformer has a turns ratio of 1 : 2, and is connected to a purely resistive load as shown in the figure. The magnetizing current drawn is 1 A, and the secondary current is 1 A. If core losses and leakage reactances are neglected, the primary current is :

1.41 A

2 A

2.24 A

3 A

Power is transferred from system A to system B by an HVDC link as shown in the figure. If the voltages are as indicated in the figure, and I > 0 , then

A balanced three-phase voltage is applied to a star-connected induction motor, the phase to neutral voltage being V. The stator resistance, rotor resistance referred to the stator, stator leakage reactance, rotor leakage reactance referred to the stator, and the magnetizing reactance are denoted by respectively. The magnitude of the starting current of the motor is given by

Consider a step voltage wave of magnitude 1pu travelling along a lossless transmission line that terminates in a reactor. The voltage magnitude across the reactor at the instant the travelling wave reaches the reactor is :

- 1 pu

1 pu

2 pu

3 pu

Consider two buses connected by an impedance of . The bus 1 voltage is , and bus 2 voltage is . The real and reactive power supplied by bus 1, respectively, are

1000 W, 268 VAr

- 1000 W, -134 VAr

276.9 W, – 56.7 VAr

276.9 W, 56.7 VAr

A three-phase, 33 kV oil circuit breaker is rated 1200 A, 2000 MVA, 3 s. The symmetrical breaking current is :

1200 A

3600 A

35 kA

104.8 kA

Consider a stator winding of an alternator with an internal high-resistance ground fault. The currents under the fault condition are as shown in the figure. The winding is protected using a differential current scheme with current transformers of ratio 400/5 A as shown. The current through the operating coil is :

0.17875 A

0.2A

0.375A

60 kA

The zero-sequence circuit of the three phase transformer shown in the figure is :

Given that the op-amp is ideal, the output voltage is :

4 V

6 V

7.5 V

12.12 V

Assuming that the diodes in the given circuit are ideal, the voltage is :

5 V

The power electronic converter shown in the figure has a single-pole double-throw switch. The pole P of the switch is connected alternately to throws A and B. The converter shown is a

step-down chopper (buck converter)

half-wave rectifier

step-up chopper (boost converter)

full-wave rectifier

Figure shows a composite switch consisting of a power transistor (BJT) in series with a diode. Assuming that the transistor switch and the diode are ideal, the I-V characteristic of the composite switch is :

The fully controlled thyristor converter in the figure is fed from a single-phase source. When the firing angle is , the dc output voltage of the converter is 300 V. What will be the output voltage for a firing angle of , assuming continuous conduction ?

150 V

210 V

300 V

100 V

At t = 0, the function has

a minimum

a discontinuity

a point of inflection

a maximum

A box contains 4 white balls and 3 red balls. In succession, two balls are randomly selected and removed from the box. Given that the first removed ball is white, the probability that the second removed ball is red is :

1/3

3/7

1/2

4/7

An eigenvector of P = is :

For the differential equation with initial conditions x(0) =1 and , the solution is :

For the set of equations, The following statement is true

Only the trivial solution exists

There are no solutions

A unique non-trivial solution exists

Multiple non-trivial solutions exist

x(t) is a positive rectangular pulse from t = -1 to t = +1 with unit height as shown in the figure. The value of { where X is the Fourier transform of x(t) } is :

2

4

Given the finite length input x[n] and the corresponding finite length output y[n] of an LTI system as shown below, the impulse response h[n] of the system is :

If the resistor draws a current of 1A as shown in the figure, the value of resistance R is :

The two-port network P shown in the figure has ports 1 and 2, denoted by terminals (a, b) and (c, d), respectively. It has an impedance matrix Z with parameters denoted by . A 1W resistor is connected in series with the network at port 1 as shown in the figure. The impedance matrix of the modified two-port network (shown as a dashed box) is :

The Maxwell’s bridge shown in the figure is at balance. The parameters of the inductive coil are

The frequency response of G(s) = 1/ [s(s +1)(s + 2)] plotted in the complex G plane (for 0 ) is :

The system x = Ax + Bu with , is :

stable and controllable

stable but uncontrollable

unstable but controllable

unstable and uncontrollable

The characteristic equation of a closed-loop system is s(s +1)(s + 3) + k(s + 2) = 0 , k > 0. Which of the following statements is true ?

Its roots are always real

It cannot have a breakway point in the range – 1 < Re[s] < 0

Two of its roots tend to infinity along the asymptotes Re[s] = – 1

It may have complex roots in the right half plane.

A 50 Hz synchronous generator is initially connected to a long lossless transmission line which is open circuited at the receiving end. With the field voltage held constant, the generator is disconnected from the transmission line. Which of the following may be said about the steady state terminal voltage and field current of the generator ?

The magnitude of terminal voltage decreases, and the field current does not change

The magnitude of terminal voltage increases, and the field current does not change

The magnitude of terminal voltage increases, and the field current increases

The magnitude of terminal voltage does not change, and the field current decreases

A separately excited dc machine is coupled to a 50Hz, three-hase, 4-pole induction machine as shown in the figure. The dc machine is energized first and the machines rotate at 1600 rpm. Subsequently the induction machine is also connected to a 50Hz, three-phase source, the phase sequence being consistent with the direction of rotation. In steady state,

Both machines act as generators

The dc machine acts as a generator, and the induction machine acts as a motor

The dc machine acts as a motor, and the induction machine acts as a generator

Both machines act as motors

A balanced star-connected and purely resistive load is connected at the secondary of a star-delta transformer as shown in the figure. The line-to-line voltage rating of the transformer is 110V/220V. Neglecting the non-idealities of the transformer, the impedance ‘Z’ of the equivalent star-connected load, referred to the primary side of the transformer, is :

Consider a three-phase, 50 Hz, 11 kV distribution system. Each of the conductors is suspended by an insulator string having two identical porcelain insulators. The self capacitance of the insulator is 5 times the shunt capacitance between the link and the ground, as shown in the figure. The voltage across the two insulators are

e1 = 3.74 kV, e2 = 2.61 kV

e1 = 3.46 kV, e2 = 2.89 kV

e1 = 6.0 kV, e2 = 4.23 kV

e1 = 5.5 kV, e2 = 5.5 kV

Consider a three-core, three-phase, 50Hz, 11kV cable whose conductors are denoted as R, Y and B in the figure. The inter-phase capacitance (C1) between each pair of conductors is and the capacitance between each line conductor and the sheath is . The per-phase charging current is :

2.0 A

2.4 A

2.7 A

3.5 A

For the power system shown in the figure below, the pecifications of the components are the following :G1: 25 kV, 100 MVA, X = 9%G2: 25 kV, 100 MVA, X = 9%T1: 25 kV/220 kV, 90 MVA, X = 12%T2: 220kV/ 25 kV, 90 MVA, X = 12%Line1: 220 kV, X = 150 ohms

The transistor circuit shown uses a silicon transistor with and a dc current gain of 100. The value of is :

4.65 V

6.3 V

7.23 V

The TTL circuit shown in the figure is fed with the waveform X (also shown). All gates have equal propagation delay of 10 ns. The output Y of the circuit is :

When a “CALL Addr” instruction is executed, the CPU carries out the following sequential operations internally:Note :(R) means content of register R((R)) means content of memory location pointed to by RPC means Program CounterSP means Stack Pointer

(SP)incremented(PC) Addr((SP)) (PC)

(PC) Addr((SP)) (PC)(SP)incremented

(PC) Addr(SP)incremented((SP)) (PC)

((SP)) (PC)(SP ) incremented(PC) Addr

Directions for next two questions: A separately excited DC motor runs at 1500 rpm under no-load with 200 V applied to the armature. The field voltage is maintained at its rated value. The speed of the motor, when it delivers a torque of 5 Nm, is 1400 rpm as shown in the figure. The rotational losses and armature reaction are neglected.

For the motor to deliver a torque of 2.5 Nm at 1400 rpm, the armature voltage to be applied is :

125.5 V

193.3 V

200 V

241.7 V

Directions for next two questions: Given f (t) and g(t) as shown below :

The Laplace transform of g(t) is :

Directions for next two questions: The following Karnaugh map represents a function F.

Which of the following circuits is a realization of the above function F ?

Directions for next two questions: The L-C circuit shown in the figure has an inductance L = 1 mH and a capacitance C = 10 F.

The L-C circuit of Q.54 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 :

25 persons are in a room. 15 of them play hockey, 17 of them play football and 10 of them play both hockey and football. Then the number of persons playing neither hockey nor football is :

17

13

Choose the most appropriate word from the options given below to complete the following sentence :If we manage to _______ our natural resources, we would leave a better planet for our children.

uphold

restrain

cherish

conserve

The question below consists of a pair of related words followed by four pairs of words. Select the pair that best express the relation in the original pair.Unemployed : Worker

fallow : land

unaware : sleeper

wit : jester

renovated : house

Which of the following options is the closest in meaning to the word below :Circuitous

cyclic

indirect

confusing

crooked

Choose the most appropriate word from the options given below to complete the following sentence :His rather causal remarks on politics ________ his lack of seriousness about the subject.

masked

belied

betrayed

suppressed

Hari (H), Gita (G), Irfan (I) and Saira (S) are sibiligs (i.e. brothers and sisters). All were born on 1st January. The age difference between any two successive siblings (that is born one after another) is less than3 years. Given the following facts :i. Hair’s age + Gita’s age > Irfan’s age + Saira’s age.ii. The age difference between Gita and Saira is 1 year. However, Gita is not the oldest and Saira is not the youngest.iii. There are not twins.In what order were they born (oldest first) ?

HSIG

SGHI

IGSH

IHSG

5 skilled workers can build a wall in 20 days; 8 semi-skilled worker can build a wall in 25 days; 10 unskilled workers can build a wall in 30 days. If a team has 2 killed, 6 semi-skilled and 5 unskilled workers, how long will it take to build the wall ?

20 days

18 days

16 days

15 days

Modern warfare has changed from large scale clashes of armies to suppression of civilian populations. Chemical agents that do their work silently appear to be suited to such warfare; and regretfully, there exist people in military establishments who think that chemical agents are useful tools for their cause.Which of the following statements best sums up the meaning of the above passage :

Modern warfare has resulted in civil strife.

Chemical agents are useful in modern warfare.

Use of chemical agents in warfare would be undesirable.

Given digits 2, 2, 3, 3, 3, 4, 4, 4, 4 how many distinct 4 digit numbers greater than 3000 can be formed ?

50

51

52

54

If 137 + 276 = 435 how much is 731 + 672 ?

534

1403

1623

1513

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