In three-phase squirrel-cage induction motors____________?
(A) rotor conductor ends are short-circuited through slip rings
(B) rotor conductors are short-circuited through end rings
(C) rotor conductors are kept open
(D) rotor conductors are connected to insulation
The maximum torque in an induction motor depends on___________?
(A) frequency
(B) rotor inductive reactance
(C) square of supply voltage
(D) all of the above
An induction motor is__________?
(A) self-starting with zero torque
(B) self-starting with high torque
(C) self-starting with low torque
(D) non-self starting
If any two phases for an induction motor are interchanged_______?
(A) the motor will run in reverse direction
(B) the motor will run at reduced speed
(C) the motor will not run
(D) the motor will burn
As load on an induction motor goes on increasing______________?
(A) its power factor goes on decreasing
(B) its power factor remains constant
(C) its power factor goes on increasing even after full load
(D) its power factor goes on increasing up to full load and then it falls again
Slip ring motor is recommended where____________?
(A) speed control is required
(B) frequent starting, stopping and reversing is required
(C) high starting torque is needed
(D) all above features are required
In an induction motor the relationship between stator slots and rotor slots is that_____________?
(A) stator slots are equal to rotor slots
(B) stator slots are exact multiple of rotor slots
(C) stator slots are not exact multiple of rotor slots
(D) none of the above
Low voltage at motor terminals is due to____________?
(A) inadequate motor wiring
(B) poorely regulated power supply
(C) any one of the above
(D) none of the above
A 3-phase induction motor delta connected is carrying too heavy load and one of its fuses blows out. Then the motor______________?
(A) will continue running burning its one phase
(B) will continue running burning its two phase
(C) will stop and carry heavy current causing permanent damage to its winding
(D) will continue running without any harm to the winding
A 3-phase induction motor stator delta connected, is carrying full load and one of its fuses blows out. Then the motor_______________?
(A) will continue running burning its one phase
(B) will continue running burning its two phases
(C) will stop and carry heavy current causing permanent damage to its winding
(D) will continue running without any harm to the winding