The starting torque in case of centrifugal pumps is generally
A. Less than running torque
B. Same as running torque
C. Slightly more than running torque
D. Double the running torque
Answer: Option A
A. Less than running torque
B. Same as running torque
C. Slightly more than running torque
D. Double the running torque
Answer: Option A
Rotor of a motor is usually supported on _________ bearings.
A. Ball or roller
B. Needle
C. Bush
D. Thrust
When the load is above _________ a synchronous motor is found to be more economical.
A. 2 kW
B. 20 kW
C. 50 kW
D. 100 kW
For derris and winches which of the following drives can be used?
A. Pole changing squirrel cage motors
B. D.C. motors with Ward-Leonard control
C. A.C. slip ring motors with variable resistance
D. Any of the above
Which of the following motors is preferred for traction work?
A. Universal motor
B. D.C. series motor
C. Synchronous motor
D. Three-phase induction motor
Reason