A 3 phase, 400 V, 5 k W, star connected synchronous motor having an internal reactance of 10 W is operating at 50% load, unity pf. Now, the excitation is increased by 1%. What will be the new load in percent, if the power factor is to be kept same? Neglect all losses and consider

A 3 phase, 400 V, 5 k W, star connected synchronous motor having an in

1.	A 3 phase, 400 V, 5 k W, star connected synchronous motor having an internal reactance of 10 W is operating at 50% load, unity pf. Now, the excitation is increased by 1%. What will be the new load in percent, if the power factor is to be kept same? Neglect all losses and consider
A.	67.9%
B.	56.9%
C.	51%
D.	50%
Answer» B. 56.9%

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A 3 phase, 400 V, 5 k W, star connected synchronous motor having an internal reactance of 10 W is operating at 50% load, unity pf. Now, the excitation is increased by 1%. What will be the new load in percent, if the power factor is to be kept same? Neglect all losses and consider

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