D.C. Motors

A. back e.m.f. is less than the applied voltage
B. back e.m.f. is equal to the applied voltage
C. back e.m.f. of rotor is more than the applied voltage
D. none of the above

A. field control method
B. armature controlled method
C. field diverter
D. frequency control method

A. Swinburne test
B. Hopkinson test
C. Brake test
D. Field test

A. decrease in speed
B. increase in speed
C. short circuit
D. open circuit

A. series with field winding
B. series speed armature winding
C. parallel big field winding
D. parallel with armature winding

A. not develop starting torque
B. fail to start without load
C. run at dangerously high speed
D. draw more current without producing sufficient torque

A. voltage control method
B. flux control method
C. rheostat control method
D. all of the above

If the field winding resistance of a DC shunt motor is increases, its speed will
A. decreases
B. increases
C. remains same
D. none of the above

A. decreases
B. increases
C. remain same
D. none of the above

A. decreases.
B. increases
C. remain same
D. none of the above