A dc series motor of resistance 1 Ω across terminals runs at 1000 rpm – McqOptions

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1.	A dc series motor of resistance 1 Ω across terminals runs at 1000 rpm at 250 V taking a current of 20 A. When an additional resistance of 6 Ω is inserted in series and taking the same current, the new speed would be
A.	142.8 rpm
B.	166.7 rpm
C.	478.3 rpm
D.	956.6 rpm
Answer» D. 956.6 rpm

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