A. sR2X2 = 1
B. sR2 = X2
C. R2 = sX2
D. R2 = s2X2
Related Mcqs:
- The torque of a rotor in an induction motor under running condition is maximum__________?
A. at the unit value of slip
B. at the zero value of slip
C. at the value of the slip which makes rotor reactance per phase equal to the resistance per phase
D. at the value of the slip which makes the rotor reactance half of the rotor - A 3-phase 440 V, 50 Hz induction motor has 4% slip. The frequency of rotor e.m.f. will be____________?
A. 200 Hz
B. 50 Hz
C. 2 Hz
D. 0.2 Hz - If a 3-phase supply is given to the stator and rotor is short circuited rotor will move___________?
A. in the opposite direction as the direction of the rotating field
B. in the same direction as the direction of the field
C. in any direction depending upon phase squence of supply - Insertion of resistance in the rotor of an induction motor to develop a given torque?
A. decreases the rotor current
B. increases the rotor current
C. rotor current becomes zero
D. rotor current rernains same - Insertion of reactance in the rotor circuit_______?
A. reduces starting torque as well as maximum torque
B. increases starting torque as well as maximum torque
C. increases starting torque but maxi-mum torque remains unchanged
D. increases starting torque but maxi-mum torque decreases - The shape of the torque/slip curve of induction motor is__________?
A. parabola
B. hyperbola
C. rectangular parabola
D. straigth line - The stating torque of the slip ring induction motor can be increased by adding__________?
A. external inductance to the rotor
B. external resistance to the rotor
C. external capacitance to the rotor
D. both resistance and inductance to rotor - In Ns is the synchronous speed and s the slip, then actual running speed of an induction motor will be___________?
A. Ns
B. s.N,
C. (l-s)Ns
D. (Ns-l)s - 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 - Slip rings are usually made of___________?
A. copper
B. carbon
C. phospor bronze
D. aluminium
