Machine Design Multiple Choice Questions on “Flywheel”.
1. Is use of a flywheel recommended when a large motor is required only for a small instant of time?
a) True
b) False
Answer: a
Clarification: Fly wheel allows the large motor to be replaced by a smaller motor as the peak power is required only for a small instance of time and not through the entire operation.
2. Flywheels are used in punching and shear operation.
a) True
b) False
Answer: a
Clarification: Flywheels store the kinetic energy imparted during idle positions and delivers this energy during actual shearing or punching.
3. Which of the following are functions of flywheel?
a) Store and release energy during work cycle
b) Reduce power capacity of the electric motor
c) Reduce amplitude of speed fluctuations
d) All of the listed
Answer: d
Clarification: Flywheel provides uniform motion by storing energy during idle positions and using this at actual operational time and thus reducing the power capacity of the electric motor.
4. When comes down to stress reduction, which one is preferred?
a) Solid flywheel
b) Split flywheel
c) Both have equal stresses
d) Cannot be determined
Answer: b
Clarification: The arms are free in split flywheel to contract and hence are better for stress reduction.
5. Flywheel and governor can be interchanged.
a) True
b) False
Answer: b
Clarification: Flywheel influences cyclic speed fluctuations while governor control mean speed.
6. If load on the engine is constant, the mean speed will be constant and ___ will not operate.
a) Flywheel
b) Governor
c) Both flywheel and governor
d) None of the mentioned
Answer: b
Clarification: Governor is used to control the mean speed and if mean speed is held constant then the governor will not operate.
7. The operation of flywheel is continuous.
a) True
b) False
Answer: a
Clarification: Flywheel is used to control the fluctuations and thus is continuously working.
8. Which of the following doesn’t waste energy?
a) Flywheel
b) Governor
c) Both flywheel and governor
d) Neither flywheel nor governor
Answer: a
Clarification: Flywheel has kinetic energy which is 100% convertible while governor suffer from friction losses.
9. Which of the following is not true for cast iron flywheels?
a) Excellent damping
b) Cheap
c) Given complex shape
d) Sudden failure
Answer: d
Clarification: Due to low tensile strength failure is sudden.
10. When the driving torque is more than load torque, flywheel is ______
a) Accelerated
b) Decelerated
c) Constant velocity
d) Can’t be determined
Answer: a
11. During the portion AB the flywheel is _____
a) Accelerated
b) Decelerated
c) Maintain constant speed
d) None of the listed
Answer: a
Clarification: Driving torque is more than the torque supplied by motor.
12. During the portion BC the flywheel is _____
a) Accelerated
b) Decelerated
c) Maintain constant speed
d) None of the listed
Answer: a
Clarification: Driving torque is lesser than the torque supplied by motor.
13. The flywheel is accelerated during the
a) AB
b) BC
c) CD
d) Both AB and CD
Answer: d
Clarification: Whenever the torque supplied by the motor is greater than the torque needed by machine, flywheel will accelerate.