GATE 2019: Revision Test 4 for ESE & GATE EE Exams

Question 1

Consider the following statements with the reference to the root loci of the characteristic equation of unity feedback control system with an open loop transfer function of G(s) =

-
1) Each locus starts at an open loop pole and ends either at an open loop zero or infinity
2) Each locus starts at an open loop pole or infinity and ends at an open loop zero
3) There are three separate root loci
4) There are five separate root loci
Which of these statements are correct?

Question 2

For the function

the magnitude of directional derivative along a line making an angle 30° with the positive x-axis at (2,0) is…..

Question 3

The rank of the matrix

Question 4

A closed-loop control system is stable if the Nyquist plot of the corresponding open-loop transfer function

Question 5

Consider the following statements regarding universal motor.
A) It is the bigger version of AC series motor.
B) The speed of a universal motor is same like as of dc series motor.
C) Universal motor is used in vacuum cleaners.
Which of the following is following option is true?

Question 6

Consider the following figure shown below.

Since

A) If K>0, steady state stability is maintained.
B) If K=0, limiting stage of steady state stability is attained.
C) If K<0, instability occurs.
Which of the following option is/are correct?

Question 7

The Fourier transform of a continuous time signal

is given by

where

and

denotes frequency. Then the value of

at

is ________(up to 1 decimal place). (ln denotes the logarithm to base e).

Question 8

In case of half-wave symmetry of a signal, what is the correct statement regarding the value of the Fourier coefficients when n is an even number?

Question 9

An alternator requires an excitation of 3A to produce on SC its full load current of 70A. The same excitation on OC gives an emf of 250V. If the resistance of armature is 0.793Ω and of the ammeters and lead used in the SC test 0.007Ω. What is the full load regulation on non-inductive load if the terminal pd on full load is 1100V.

Question 10

As shown in the figure, C is the arc from the point (3, 0) to the point (0, 3) on the circle

The value of the integral

is ________ (upto 2 decimal places).

Question 11

The incidence matrix of a graph is as given below
A=

The number of possible trees is

Question 12

A 3-

, 12 kW, 440 V, 4 pole , 50 Hz, star connected motor draws 20 A on full load. Its no load and blocked rotor test data are given below.
No load test : 440 V, 6 A, 1002 W
Blocked rotor test : 100 V, 15 A, 750 W
Neslecting copper loss in no load test and core loss in blocked rotor test estimate motor full load efficiency.

Question 13

The armature resistance of dc motor is 0.4 ohm at no load, the motor draws 2 A from a supply voltage of 40 V and runs at 1500 rpm. the efficiency of the motor while it is operating on load at 1500 rpm drawing a current of 4 A from the same source will be

Question 14

A voltage source of 50∟(-23.96˚) V is connected parallel across a choke of resistance 6Ω and inductive reactance of 8Ω. If an impedance of 3-j4 is connected parallel across the choke then the magnitude of the current supplied (in Amp) by the voltage source is

Question 15

The fuel characteristics of two generators

Generator-1:

Generator-2:

If these generators are supplying a common load of 600MW and 100MW, 500MW are the minimum and maximum limit for the generators. Then what will be the economic load schedule of generator-2 (in MW).

Question 16

A 3-

, 50 Hz transmission line consists of three equal conductor of radii & placed in a horizontal plance, with a spacing of 6 m between the middle and each outer conductor as shown in fig. what is the inductive reactance per phase per km of the transposed line if the radius of each conductor is 12.5 mm.