A dc shunt motor runs at 600 rpm from a 240 V supply. Its armature has – McqOptions

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1.	A dc shunt motor runs at 600 rpm from a 240 V supply. Its armature has a resistance of 0.5 ohm and draws 30 amp. If an external resistance of 2.5 ohm is connected in series with the armature, while there is no change in armature or filed current, the new speed is
A.	400 rpm
B.	800 rpm
C.	600 rpm
D.	None of these
Answer» B. 800 rpm

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