A generator develops an e.m.f. of 130 V and has a terminal potential difference of 125 V, when the armature current is 25 A. The resistance of the armature is

$ 0.2\Omega$ $0.25 \Omega$ $0.4 \Omega$ None

$ 0.2\Omega$

$ R = \frac{E - V}{I} = \frac{130 - 125}{25} = 0.2 \Omega $