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A six pole generotar with fixed field ex...

A six pole generotar with fixed field excitation developes an e.m.f. of `100 V` when operating at `1500` r.p.m. At what speed must it rotate to develop `120 V`?

A

1200 rpm

B

1800 rpm

C

1500 rpm

D

400 rpm

Text Solution

Verified by Experts

The correct Answer is:
B
`e = B N A omega`
So `E prop omega`
New speed = `(120)/100 xx 1500 = 1800 rp m `.
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