In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to
A)100% of the previous value
B)50% of the previous value
C)25% of the previous value
D)10% of the previous value

Question

Quizplus · Accepted Answer

In a DC series motor, the torque (T) is directly proportional to the square of the armature current (I), i.e., T ∝ I^2. Therefore, if the armature current is reduced by 50%, the new torque will be (0.5I)^2 = 0.25I^2, which is 25% of the previous value.

In a DC Series Motor, If the Armature Current Is Reduced by Reduced