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An electric motor turns on DC source of ...

An electric motor turns on DC source of emf 200 V and drawn a current of 10 A. If the efficiency be `40%`, then the resistance of armature is

A

`5 Omega`

B

`12 Omega`

C

`30 Omega`

D

`25 Omega`

Text Solution

Verified by Experts

The correct Answer is:
B
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