A single phase induction motor is
The capacitor in a capacitor-start induction run ac motor is connected in series with
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Which of the following statements associated with shaded pole induction motor is incorrect?
Assertion (A) : In a single phase induction motor, while the motor is connected to single phase ac supply and is rotating, the two fields (stator and rotor field) combine to form a resultant rotating field revolving at a synchronous speed.
Reason (R) : The rotor field created by rotor currents acts at right angle to the stator field and also lags the stator field by 90° electrical degrees in time phase.
Assertion (A) : Linear induction motor wide use in industry and electric traction.
Reason (R) : Linear induction motors are cheaper in initial as well as in maintenance costs.
In comparison to a resistance start motor, the capacitor start motor has
1. high starting torque
2. high running torque
3. larger phase difference between two winding currents
4. low starting current
Out of these, the correct answer is
The direction of rotation of a shaded pole induction motor
In various types of split-phase, 1-phase induction motors, the starting torques produced are in the following descending order.
Which of the following statements associated with an ac series motor is incorrect?
A single phase reluctance motor
The torque of a reluctance motor can be effectively decreased by
In a single phase hysteresis motor
Match List-I (Type of motors) with List-ll (Application) and select the correct answer using the codes given below the lists:
List-I
A. Shaded pole motor
B. Reluctance motor
C. Universal motor
D. Single phase IM
List-ll
1. Ceiling fan
2. Food mixture
3. Timing and control purposes
4. Toys
Codes:
A B C D
(a) 4 3 2 1
(b) 2 3 1 4
(c) 3 4 2 1
(d) 2 1 3 4
Which of the following single phase motor has no teeth or winding?
Match List-I (Type of motors) with List-ll (Characteristics) and select the correct answer using the codes given below the lists:
List-I
A. Shaded Pole motor
B. Hysteresis motor
C. PMDC motor
D. Capacitor start motor
List-ll
1. Least noise
2. Highest starting torque
3. Lowest speed
4. Used in cassette tape recorder
Codes:
A B C D
(a) 3 4 2 1
(b) 1 4 2 3
(c) 3 1 4 2
(d) 1 2 3 4
Assertion (A): When a ceiling fan using a capacitor run motor is switched on, it hums but does not run. When it is driven by some external means it runs in the direction in which it was made to run.
Reason (R): The capacitor connected in series with the auxiliary winding is short circuited.
The rotor of a stepper motor has
A stepping motor has four concentric coils on its 4-pole stator. It has an unwound variable reluctance motor with 5 teeth. The step angle for this motor is
A single phase induction motor is running at N rpm. Its synchronous speed is Ns. If its slip w.r.t forward field is s. What is the slip w.r.t. the backward field?