A 220 V. DC shunt motor is operating at a speed of 1,440 rpm.
The armature resistance is 1.0 Ω and armature current is 10 A.
If the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be
A. 1.79Ω
B. 2.1Ω
C. 3.1Ω
D. 18.9Ω
Show Answer
Answer: A
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