1. In an Induction motor slip depends on
a) Supply frequency
b) Rotor input power
c) Rotor copper loss
d) both (b) and (c)
2. The no-load current in an induction motor is approximately __ percentage of the full load current?
a) much lower
b) much higher
c) slightly less
d) slightly more
3. In an induction motor, the variable mechanical load is represented electrically by a variable __ only
a) Inductance
b) Capacitance
c) Resistance
d) Both Inductance and Resistance
4. The power factor of the 3 phase induction motor will be maximum when it operates at:
a) Full load
b) No-load
c) Maximum slip
d) Maximum torque
5. In Induction motors, the short circuit test is __ test
a) no load
b) blocked rotor
c) stator resistance
d) open circuit
6. When the induction motor is stand still the slip will be:
a) zero
b) one
c) infinity
d) 0.5
7. Circle diagram is employed to determine the performance of the:
a) both Induction motor and synchronous motor
b) only induction motor
c) only synchronous motor
d) can be applied for any machine
8. The crawling occurs in the induction motor due to:
a) low supply voltage
b) imbalance in supply voltage
c) harmonics developed in motor
d) can occur because of wither low voltage and imbalance in supply voltage
9. Increase in the length of air gap in an induction motor causes:
a) decreases the power factor
b) decreases the pulsating losses
c) increase the ampere turns required to produce same flux density
d) All the above
10. The rotor slots of the 3 phase induction motor are inclined. This phenomenon is known as:
a) skewing
b) crawling
c) cogging
d) none of the above
a) Supply frequency
b) Rotor input power
c) Rotor copper loss
d) both (b) and (c)
2. The no-load current in an induction motor is approximately __ percentage of the full load current?
a) much lower
b) much higher
c) slightly less
d) slightly more
3. In an induction motor, the variable mechanical load is represented electrically by a variable __ only
a) Inductance
b) Capacitance
c) Resistance
d) Both Inductance and Resistance
4. The power factor of the 3 phase induction motor will be maximum when it operates at:
a) Full load
b) No-load
c) Maximum slip
d) Maximum torque
5. In Induction motors, the short circuit test is __ test
a) no load
b) blocked rotor
c) stator resistance
d) open circuit
6. When the induction motor is stand still the slip will be:
a) zero
b) one
c) infinity
d) 0.5
7. Circle diagram is employed to determine the performance of the:
a) both Induction motor and synchronous motor
b) only induction motor
c) only synchronous motor
d) can be applied for any machine
8. The crawling occurs in the induction motor due to:
a) low supply voltage
b) imbalance in supply voltage
c) harmonics developed in motor
d) can occur because of wither low voltage and imbalance in supply voltage
9. Increase in the length of air gap in an induction motor causes:
a) decreases the power factor
b) decreases the pulsating losses
c) increase the ampere turns required to produce same flux density
d) All the above
10. The rotor slots of the 3 phase induction motor are inclined. This phenomenon is known as:
a) skewing
b) crawling
c) cogging
d) none of the above
