Countercurrent Braking MCQs : This section focuses on the "Countercurrent Braking". These Multiple Choice Questions (MCQs) should be practiced to improve the Countercurrent Braking skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
All loops are meshes.
A. True
B. False
Question 2
Braking resistance should be selected in order to limit the braking current.
A. True
B. False
Question 3
Calculate the bandwidth in series RLC circuit if the frequency is 20 Hz and the quality factor is 5.
A. 2 Hz
B. 4 Hz
C. 6 Hz
D. 8 Hz
Question 4
Calculate the current in DC shunt field winding using the following data: Ia=15 A, IL=21, R=22, N=484.
A. 4 A
B. 2 A
C. 7 A
D. 6 A
Question 5
Calculate the equivalent capacitance when two capacitors are connected in parallel of values 8 F, 7 F.
A. 15 F
B. 20 F
C. 40 F
D. 7 F
Question 6
Calculate the equivalent resistance when two resistances are connected in parallel of values 2 ?, 2 ?.
A. 1 ?
B. 2 ?
C. 4 ?
D. 7 ?
Question 7
Calculate the flux produced by the DC shunt field winding using the following data: Ia=5 A, IL=11, R=2, N=4.
A. 14 Wb
B. 12 Wb
C. 17 Wb
D. 18 Wb
Question 8
Calculate the quality factor for the resistor.
A. inf
B. 0
C. 1
D. 0.7
Question 9
Calculate the total energy stored in the inductor if the current value is 4 A and inductance values are 1 H and 2 H.
A. 72 J
B. 22 J
C. 82 J
D. 24 J
Question 10
Calculate the value of the inductive reactance during resonance if the value of capacitive reactance is 2 ohm.
A. 8 ?
B. 2 ?
C. 3 ?
D. 1 ?
Question 11
DC shunt motors are used where the high _________ is required.
A. Starting torque
B. Maximum torque
C. Minimum torque
D. Breakdown torque
Question 12
Full form of IFOC.
A. Indirect field oriented control
B. Inverter field oriented control
C. Isolated field oriented control
D. Insight field oriented control
Question 13
Full form of TVR is _________
A. Terminal voltage reversal
B. Total voltage reversal
C. Terminal voltage redirect
D. Total voltage reversal
Question 14
In DC shunt machine ? is directly proportional to Ia.
A. True
B. False
Question 15
Mesh analysis is only applied to the planar circuits.
A. True
B. False
Question 16
Plugging is suitable for __________ type loads.
A. Gravitational
B. Electrostatic
C. Weightless
D. Leading
Question 17
Selectivity value increases for lower values of bandwidths.
A. True
B. False
Question 18
The characteristics shown by an element in the I-V curve is a straight line passing through the origin with a positive slope. The nature of the element is _______
A. Non-linear, Bilateral
B. Linear, Unilateral
C. Linear, Bilateral
D. Non-linear, Unilateral
Question 19
The minimum value of the admittance in case of the parallel RLC network is ___________
A. R
B. 1÷R
C. Xl-Xc
D. Xc
Question 20
The nodal method is better than mesh analysis for solving circuit problems.
A. True
B. False
Question 21
The relationship between the torque(T) and power(P) developed in the DC shunt motor is ___________ (Neglecting all the losses)
A. T ? ?P
B. T ? P2
C. T ? ?P
D. T ? P
Question 22
The shape of the current-torque characteristics in DC shunt motor is __________
A. Rectangular Hyperbola
B. Parabola
C. Straight line
D. Ellipse
Question 23
The shape of the speed-armature current characteristics in DC shunt motor is __________
A. Hyperbolic
B. Parabola
C. Negative slope linear line
D. Ellipse
Question 24
The shape of the speed-torque characteristics in DC shunt motor is __________
A. Rectangular Hyperbolic
B. Whole x-y plane
C. Circle
D. Ellipse
Question 25
The value of current at time of starting is ___________
A. High
B. Low
C. Very low
D. 0
Question 26
The value of impulse at t=0 is __________
A. 0
B. 2
C. 1
D. infinite
Question 27
The value of unit step function at t=5 sec is ________
A. 0
B. 1
C. -1
D. 2
Question 28
Torque developed in the motor is ___________
A. Km?Ia
B. Km?Ia3
C. 2Km?Ia
D. Km?Ia2
Question 29
Calculate the current in DC shunt field winding using the following data: Ia=15 A, IL=21, R=22, N=484.
A. 4:00 AM
B. 2:00 AM
C. 7:00 AM
D. 6:00 AM
Question 30
Calculate the equivalent resistance when two resistances are connected in parallel of values 2 Ω, 2 Ω.
A. 1 Ω
B. 2 Ω
C. 4 Ω
D. 7 Ω
Question 31
Calculate the value of the inductive reactance during resonance if the value of capacitive reactance is 2 ohm.
A. 8 Ω
B. 2 Ω
C. 3 Ω
D. 1 Ω
Question 32
In DC shunt machine ∅ is directly proportional to Ia.
A. TRUE
B. FALSE
Question 33
The relationship between the torque(T) and power(P) developed in the DC shunt motor is ___________ (Neglecting all the losses)
A. T ∝ √P
B. T ∝ P2
C. T ∝ ∛P
D. T ∝ P
Question 34
Torque developed in the motor is ___________
A. KmΦIa
B. KmΦIa3
C. 2KmΦIa
D. KmΦIa2