A dc series motor with a resistance between terminals of 1 Ω, runs at – McqOptions

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1.	A dc series motor with a resistance between terminals of 1 Ω, runs at 800 rpm from a 200 V supply taking 15 A. If the speed is to be reduced to 475 rpm for the same supply voltage and current the additional series resistance to be inserted would be approximately
A.	2.5 Ω
B.	3 Ω
C.	4.5 Ω
D.	5 Ω
Answer» E.

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