A generator has armature resistance of $0 .1\,\Omega $ and develops an induced emf of $120 \,V$ when driven at its rated speed. Its terminal voltage when a current of $50\,A$ is being drawn is ................. $V$
A$120$
B$5$
C$115$
D$70$
AIEEE 2012, Medium
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C$115$
c Armature resistance $R=0.1\, \Omega$
Induced emf, $e=120\, \mathrm{V}$
Current drown, $I=50\, \mathrm{A}$
We know that,
$e=V+I R$
or, $V=e-I R=120-50 \times 0.1=115 \,V$
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