1. Rectifiers are used to convert DC power into variable AC power.
A. True
B. False
Answer: B
Inverters are used to convert DC power into variable AC power. The variable AC power means variable frequency and variable voltage level.
2. Short circuit problem is severe in case of current source inverter.
A. True
B. False
Answer: B
Short-circuit problem is severe in the case of voltage source inverter. The output voltage of VSI is fixed but the output current depends upon the load. When Z=0, I=V÷Z=∞.
3. Full form of KERS is ___________
A. The kinetic energy recovery system
B. The kinetic ever recovery system
C. Kin ever recovery system
D. The kinetic energy recovery store
Answer: A
The full form of KERS is the Kinetic energy recovery system. The systems recover the kinetic energy from the heat generated by the car’s braking.
4. Full form of IGBT is ___________
A. Insulated gate bipolar transistor
B. Insulated gate bipolar transducer
C. Insulator gate bidirectional transducer
D. Insulated gate bidirectional transistor
Answer: A
The full form of IGBT is an Insulated gate bipolar transistor. It is a 3-terminal device, bipolar in nature. It can be used as a switch.
5. Flywheel is analogous to ___________
A. Chemical battery
B. Mechanical battery
C. Nuclear battery
D. Electrostatic battery
Answer: B
A flywheel is a heavy wheel that stores a high amount of rotational kinetic energy. It requires a lot of force to spin the wheel.
6. Energy is stored in Flywheel in the form of __________
A. Kinetic energy
B. Electrical energy
C. Solar energy
D. Wind energy
Answer: A
Energy is stored in Flywheel in the form of kinetic energy. It stores rotational kinetic energy.
7. Calculate the coefficient of fluctuation of speed using the data: Vmax(Fluctuation)=25 m/sec, Vmean=12 m/sec.
A. 2.08
B. 2.16
C. 2.34
D. 2.74
Answer: A
The coefficient of fluctuation of speed is the ratio of the maximum fluctuation speed and mean speed.
C.F = Vmax(Fluctuation) ÷ Vmean = 25÷12 = 2.08.
8. Calculate the maximum fluctuation of speed using the data: Vmax=23 m/sec, Vmin=13 m/sec.
A. 12
B. 10
C. 14
D. 15
Answer: B
The maximum fluctuation of speed is the difference between the maximum speed and minimum speed. Maximum fluctuation of speed
= Vmax – Vmin = 23 – 13 = 10.
9. Calculate the Kinetic energy of the object of mass = 7 Kg moving in a straight line with a velocity of 12 m/s.
A. 504 J
B. 502 J
C. 503 J
D. 509 J
Answer: A
The Kinetic energy of the object of mass = 7 Kg moving in a straight line with a velocity of 12 m/s is
.5×m×v2 = .5×7×12×12 = 504 J.
10. Calculate the rotational kinetic energy of the object using the data: I=5 Kg-m2, ω=25 rad/sec.
A. 1.46 KJ
B. 1.56 KJ
C. 2.58 KJ
D. 3.15 KJ
Answer: B
The Kinetic energy of the object having a moment of inertia=5 kg-m2 rotating with an angular velocity equal to 25 rad/sec is
