A 220 V, 15 kW, 1000 rpm shunt motor with armature resistance of 0.25 &ohm; , has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is

A 220 V, 15 kW, 1000 rpm shunt motor with armature resistance of 0.25

1.	A 220 V, 15 kW, 1000 rpm shunt motor with armature resistance of 0.25 &ohm; , has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is
A.	18.18% increase
B.	18.18% decrease
C.	36.36% increase
D.	36.36% decrease
Answer» E.

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A 220 V, 15 kW, 1000 rpm shunt motor with armature resistance of 0.25 &ohm; , has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is

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