To get the speed of D.C, motor below the normal without wastage of electrical energy is used?

Related Mcqs:

A three point starter is considered suitable for______________?

A. shunt motors B. shunt as well as compound motors C. shunt, compound and series motors D. all D.C. motors...

If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens__________?

A. nothing will happen to the motor B. this will make armature to take heavy current, possibly burning it C. this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses D. motor will run at very slow speed...

For a D.C. shunt motor if the excitation is changed_______________?

A. torque will remain constant B. torque will change but power will remain constant C. torque and power both will change D. torque, power and speed, all will change...

In Ward-Leonard control the lower limit of speed is imposed by________?

A. residual magnetism of the generator B. core losses of motor C. mechanical losses of motor and generator together D. all of the above...

The speed of a D.C. shunt motor is required to be more than full load speed. This is possible by______________?

A. reducing the field current B. decreasing the armature current C. increasing the armature current D. increasing the excitation current E. none of the above methods...