Starting Energy Relations MCQs : This section focuses on the "Starting Energy Relations". These Multiple Choice Questions (MCQs) should be practiced to improve the Starting Energy Relations skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
440 V, 77 A, 700 rpm DC separately excited motor having a resistance of 0.11 ohms excited by an external dc voltage source of 24 V. Calculate the torque developed by the motor on full load.
A. 453.51 N-m
B. 451.24 N-m
C. 440.45 N-m
D. 452.64 N-m
Question 2
A 3-phase induction motor runs at almost 888 rpm at no load and 500 rpm at full load when supplied with power from a 50 Hz, 3-phase supply. What is the corresponding speed of the rotor field with respect to the rotor?
A. 388 revolution per minute
B. 400 revolution per minute
C. 644 revolution per minute
D. 534 revolution per minute
Question 3
Calculate mark to space ratio if the system is on for 9 sec and time period is 11 sec.
A. 4.6
B. 4.8
C. 4.5
D. 4.9
Question 4
Calculate the active power in a 1.2 ? resistor with 1.8 A current flowing through it.
A. 3.88 W
B. 3.44 W
C. 3.12 W
D. 2.18 W
Question 5
Calculate the active power in a 157.1545 H inductor.
A. 4577 W
B. 4567 W
C. 4897 W
D. 0 W
Question 6
Calculate the moment of inertia of the thin spherical shell having a mass of 3.3 kg and diameter of .6 cm.
A. .00125 kgm2
B. .00196 kgm2
C. .00145 kgm2
D. .00178 kgm2
Question 7
Calculate the power developed by a motor using the given data: Eb = 55 V and I = 6 A.
A. 440 W
B. 220 W
C. 330 W
D. 550 W
Question 8
Calculate the time period of the waveform y(t)=7cos(54?t+2?÷4).
A. .055 sec
B. .037 sec
C. .023 sec
D. .017 sec
Question 9
Calculate the total heat dissipated in a resistor of 12 ? when 9.2 A current flows through it.
A. 2.01 KW
B. 3.44 KW
C. 1.01 KW
D. 2.48 KW
Question 10
Calculate the useful power developed by a motor using the given data: Pin= 1500 W, Ia= 6 A, Ra=.2 ?. Assume frictional losses are 50 W and windage losses are 25 W.
A. 1400 W
B. 1660.5 W
C. 1417.8 W
D. 1416.7 W
Question 11
Calculate the value of the angular acceleration of the motor using the given data: J = 36 kg-m2, load torque = 66 N-m, motor torque = 26 N-m.
A. 1.11 rad/s2
B. 2.22 rad/s2
C. 3.33 rad/s2
D. 4.44 rad/s2
Question 12
The generated e.m.f from 2-pole armature having 2 conductors driven at 3000 rpm having flux per pole as 4000 mWb, with 91 parallel paths is ___________
A. 8.64 V
B. 8.56 V
C. 8.12 V
D. 8.79 V
Question 13
The slope of the V-I curve is 15.5°. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
A. .277 ?
B. .488 ?
C. .443 ?
D. .457 ?
Question 14
Calculate the active power in a 1.2 Ω resistor with 1.8 A current flowing through it.
A. 3.88 W
B. 3.44 W
C. 3.12 W
D. 2.18 W
Question 15
Calculate the time period of the waveform y(t)=7cos(54πt+2π÷4).
A. .055 sec
B. .037 sec
C. .023 sec
D. .017 sec
Question 16
Calculate the total heat dissipated in a resistor of 12 Ω when 9.2 A current flows through it.
A. 2.01 KW
B. 3.44 KW
C. 1.01 KW
D. 2.48 KW
Question 17
Calculate the useful power developed by a motor using the given data: Pin= 1500 W, Ia= 6 A, Ra=.2 Ω. Assume frictional losses are 50 W and windage losses are 25 W.
A. 1400 W
B. 1660.5 W
C. 1417.8 W
D. 1416.7 W
Question 18
The slope of the V-I curve is 15.5°. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
A. .277 Ω
B. .488 Ω
C. .443 Ω
D. .457 Ω