GATE 2020: Toppers Quiz 27 (App update required to attempt this test) for ESE & GATE EE Exams

Question 1

For the given figure I₁=1 - j2 , I₁' = -2 - j5

Calculate the power factor at the receiving end

Question 2

A self commutating switch SW, operated at duty cycle δ is used to control the load voltage as shown in the figure

Under steady state operating conditions, the average voltage across the inductor and the capacitor respectively are.

Question 3

The starting current of 3 phase Induction motor is 7 times the rated current while the rated slip is 6%. The ratio of starting torque to full load torque is –

Question 4

If the load of 50 MW is suddenly applied then find the frequency deviation during this time when A 200 MVA alternator operated at no load at frequency of 50 Hz, it has inertia constant of 5 MWsec/MVA and governing system has a time delay of 0.6 sec.?

Question 5

Below figure shows the torque-slip characteristics of a 3-phase induction motor. It displays the motor operating in 3 modes: motoring, generating and braking.

Determine the slip of the rotor in the generating mode.

Question 6

Which of the following is the laplace transform of cos(at)sinh(at)?

Question 7

In the chopper circuit shown in figure, the input dc voltage has a constant value V_s. The output voltage V₀ is assumed ripple free. The switch S is operated with a switching time period T and a duty ratio D. What is the value of critical inductance (L_C) at the boundary of continuous and discontinuous conduction of the inductor current i_L?

Question 8

Two transformers are to be operated in parallel such that they share load in proportion to their kVA ratings. The rating of the first transformer is 1000 kVA ratings. The rating of the first transformer is 1000 kVA and its pu leakage impedance is 0.08 pu. If the rating of second transformer is 350 kVA, its pu leakage impedance is

Question 9

For the block diagram shown below, the limiting value of K for stability of inner loop is found to be X < K < Y. The overall system will be stable if and only if

Question 10

The function shown in the figure can be represented as

Question 11

An SCR has V_g-I_g characteristics given as V_g = 1.5 + 8 I_g. In a certain application, the gate voltage consists of rectangular pulses of 12 V and of duration 50 μs with duty cycle 0.2. The value of R_g series resistor in gate circuit to limit the peak power dissipation in the gate to 5 watts is

Question 12

A combinational circuit using 4 x 1 multiplexer is shown in the following diagram. The simplified expression for Z is

Question 13

An 8-pole, 50 Hz, 3-phase induction motor has a power input of 72 kW. The motor is running at a speed of 700 rpm. Determine the mechanical power developed, if the total stator loss is 800 W.

Question 14

The root locus plot for a control system is shown below:

Consider the following statements regarding the system.

1) System is stable for all positive value of K.

2) System has real and repeated poles for 0.573 < K < 7.464.

3) System has damped oscillatory response for all values of K greater than 0.573.

4) System is overdamped for 0 < K < 0.573 and K > 7.464.

Which of the following is/are correct?

Question 15

The corona loss on a particular system at 50 Hz is 2 KW/km/ph. The corona loss at 60 Hz would be ________ KW/km/ph.

Question 16

For the given NPN transistor h_fe = 100. The output voltage (V₀) is

Question 17

A six pulse cyclo-converter, fed from 3-phase, 400 V, 50 Hz source, is delivering a load current of 40 A to a single-phase resistive load. The source has an inductance of 1.2 mH per phase. The rms value of load voltage for firing angle delay of 0 ° is _________.

Question 18

For the given multi-diode circuit shown in figure below, assume that V_T = 0.7 V for each diode. Then what is the value of I_D2 and V_o respectively

Question 19

The input impedance of the permanent magnet moving coil (PMMC) voltmeter is infinite. Assuming that the diode shown in the figure below is ideal, the reading of the voltmeter in Volts is

Question 20

The two-stage amplifier shown in fig uses transistors Q1 and Q2, both having current gain β of 80 and dynamic emitter resistance, r’e, of 25 Ω each. Find out the overall voltage gain of the amplifier.

Question 21

A DC generator has a useful flux of 0.05 Wb per pole. It has 8 lap connected poles and has 600 conductors on the armature. It runs at a speed of 1200 rpm. Find the EMF generated and the speed required if same connections are made using wave winding?

Question 22

A current transformer with a bar primary has 300 turns in its secondary winding. The resistance & reactance of secondary circuit are 1.5 Ω’s and 1Ω respectively including transformer winding. With a 5A current flowing in a secondary winding the magnetizing MMF is 100 Amps and the iron losses is 1.2 watts. Determine R

Question 23

If the given signal x(n) = (3(

)-4(

))u(n) then find the z-tranform of the given signal?

Question 24

In a two-element series circuit, the voltage applied is v(t)=100sin(100πt) V and the current supplied in i(t)=6sin(100πt + 30°) A, then identify the elements

Question 25

If the Converter shown in figure has a purely resistive load of R and the delay angle is

The rectification efficiency and Form Factor (F.F) respectively are