If field current is decreased in shunt dc motor, the speed of the motor

(a) remains same.

(b) increases.

(c) decreases.

(d) none of the above.
B

4 Answers

Answer :

 increases because field current decrease and field flux decrease and N is inversely proportional field flux so speed of motor is increase

Answer :

It increases because field current is directly proportional to the flux and flux is directly proportional to the armature current which is inversely proportional to the back emf and again back emf is directly proportional to the speed.

Answer :

A

Answer :

increases

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