Question

A car battery of e.m.f. $12 V$ and internal resistance $5 \times 10^{-2} \Omega$ receives a current of $60 A$ from an external source, then terminal potential difference of battery is :-

• A. 5V
• B. 3V
• C. 15V
• D. 9V

Answer 1

Answer: (C)

15V

Answer 2

Since the battery is drawing 60 A current instead of supplying, it indicates that the battery is being charged then V = E + Ir = 12 + (60 $\times$ 5 $\times \, 10^{-2}$) = 12 + 3 = 15V