A 50 MVA, 10kV, 50 Hz, star-connected, unloaded three-phase alternator has a synchronous reactance of 1 p.u and a sub-transient reactance of 0.2 p.u If a 3-phase short circuit occurs close to the generator terminals, the ratio of initial and final values of the sinusoidal component of the short circuit current is:

A 50 MVA, 10kV, 50 Hz, star-connected, unloaded three-phase alternator

1.	A 50 MVA, 10kV, 50 Hz, star-connected, unloaded three-phase alternator has a synchronous reactance of 1 p.u and a sub-transient reactance of 0.2 p.u If a 3-phase short circuit occurs close to the generator terminals, the ratio of initial and final values of the sinusoidal component of the short circuit current is:
A.	3
B.	4
C.	2
D.	5
Answer» E.

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