A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 &ohm; 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 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armat

1.	A 220 V, DC shunt motor is operating at a speed of 1440 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.	1.79 &ohm;
B.	2.1 &ohm;
C.	3.1 &ohm;
D.	18.9 &ohm;
Answer» B. 2.1 &ohm;

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A 220 V, DC shunt motor is operating at a speed of 1440 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

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