A car battery has e.m.f. 12 volt and internal resistance

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A car battery has e.m.f. 12 volt and internal resistance 5 × 10^–2 ohm. If it draws 60 amp current, the terminal voltage of the battery will be

1. 15 volt
2. 3 volt
3. 5 volt
4. 9 volt

Correct Option: D

E = V + Ir
12 = V + 60 × 5 × 10^-2
12 = V + 3 V = 9 volt