GATE 2020: Toppers Quiz 23 (App update required to attempt this test) for ESE & GATE EE Exams

Question 1

The open loop transfer function of a unity feedback system is given as,

. The phase crossover frequency (rad/s) is ______.

Question 2

A three-phase, 11 kV, 50 Hz, 2 pole, star connected, cylindrical rotor synchronous motor is connected to an 11 kV, 50 Hz source. Its synchronous reactance is 50 Ω per phase, and its stator resistance is negligible. The motor has a constant field excitation. At a particular load torque, its stator current is 100 A at unity power factor. If the load torque is increased so that the stator current is 120 A, then the load angle (in degrees) at this load is ________.

Question 3

The content (in Hexadecimal) of some of the memory locations in an 8085A based system are given below:

The contents of stack pointer (SP), program counter (PC) and (H,L) are 2700H, 2100H and 0000H respectively. When the following sequence of instructions are executed,
2100 H: DAD SP
2101 H: PCHL
the contents of (SP) and (PC) at the end of execution will be

Question 4

A 100KVA, 7700/400V, 50Hz, 1 phase transformer took 20A and 450W at 120V in a SC test, the figures referring to HV side. What is the voltage to be applied to the HV side on full load at a
pf of 0.8 leading when the secondary terminal voltage is 330V?

Question 5

A common emitter silicon transistor amplifier with quiescent emitter current as 1mA, what will be the base biasing voltage?

Question 6

The approximate steady-state current flowing in the circuit below is

Question 7

A cage-rotor induction generator is driven successively at two speeds n₁ andn₂. The stator out-puts corresponding to these speeds are 9 kW and 4 kW respectively. The ratio

is 1.043 and synchronous speed of the generator is 750 rpm, find n₁and n₂respectively. Rotor voltage per phase at still = 150 V, neglect rotor reactance and stator resistance.

Question 8

A digital circuit is designed with three D-flip flops and an Ex-OR gate as shown in below figure. If the initial value of

was 110 then the minimum number of clock pulses required to get

as 011 is ___________.

Question 9

The three conductor of a 3-phase line are arranged at the corners of a triangle of sides 2 m, 2.5 m and 4.5 m. The inductance per phase per meter, if the diameter of each conductor is 1.24 cm and conductor are regularly transposed is

Question 10

From the circuit given below, find the operating region of the transistors T1 and T2
(V_TH=-0.4)

Question 11

A 50 Hz, 2 pole turbo generator rated 100 MVA, 33 kV has an inertia constant of 4 MJ/MVA. If the mechanical input is suddenly raised to 70 MW for an electrical load of 40 MW, then the rotor acceleration is

Question 12

A 3- ɸ full converter, fed from 3- ɸ, 440 V, 50 Hz source, is connected to load R=10 Ω, E=360 V, and large Inductance so that output current is ripple free the power delivered load for firing advance angle of 60^o is

Question 13

A 11/6.6/0.5kV, star/star/delta, three winding transformer has a magnetizing current of 3A. At rated voltages, the secondary supplies a balanced load of 300 kVA at 0.8 pf lag and tertiary supplies a balanced load of 150 kW at 0.9 pf lead. The magnitude of primary phase current (in Amp) will be

Question 14

If a feedback control system has its open loop transfer function
and its root locus plot intersects the imaginary axis at s = 0; then
the value of ‘K’ at this point will be ________.

Question 15

The transistor in the amplifier circuit shown in figure is biased at I_C=1 mA . Use V_T=26 mV ,β=200,r_b=0 and r₀

What is the required value of C_E for the circuit to have a lower cut off frequency of 10Hz is

Question 16

An IDMT type over-current relay is used to protect a feeder through a 500/1 CT. The relay has a plug setting of 125% and TMS = 0.Find the value of plug setting multiplier of the relay if a fault current of 5000 A flows through the feeder.

Question 17

A charged particle of mass 2Kg and charge 3C starts at point (1 , -2 , 0) , in an electric field 12

+ 10

at time t=1 sec . What will be the acceleration of particle.

Question 18

In the following buck converter, IGBT ‘S’ is switched at 100kHz with a duty ratio of 0.IGBT is having ON state voltage drop of 0.8V. The average conduction losses in IGBT is

Question 19

X(z) = 1 - 3z^-1, Y(z) = 1 + 2 z^-2 are Z-transforms of two signals x[n], y[n] respectively. A linear time invariant system has the impulse response h[n] defined by these two signals as h[n] = x[n - 1]^*y[n]
where * denotes discrete time convolution. Then the output of the system for the input δ[n - 1]

Question 20

A single phase transformer with a ratio of 440v/110v takes a no load current of 7A at 0.3pf lag. If the secondary supplies a current of 130A at a pf of 0.7 lagging. Estimate the current taken by the primary......

Question 21

Find the value of current I in the circuit shown in figure below:

Question 22

Find the resistance and inductance of the coil if the arms of an ac Maxwell Bridge are given as: AB and BC are non-reactive resistors of value 100 Ω each. Let DA is a standard variable reactor and value of L1 of resistance 32.7Ω and CD comprises a standard variable resistor R connected in series with a coil of unknown impedance. Balance was obtained with L1=47.8mH and R=1.36Ω?

Question 23

Figure shows the polar plot of a system. The transfer function of the system is

Question 24

A 3-phase overhead line has reactance of 20 Ω. The load at receiving end is 30 MW at 0.85 pf lagging at 33 kV & it is desired to maintain 33 kV at each end by adding a compensating equipment at receiving end then the VAR rating of equipment is

Question 25

A 220 V, 110 A, 1500 rpm, DC shunt motor has negligible field resistance and 0.4 ohm armature resistance. If the motor is started using four step starter i.e. four resistance elements and five studs with armature current limited to 1.4 p.u. Calculate resistance in per unit of first and fourth steps.