MCQ
Two cells, e.m.f. of each is $E$ and internal resistance $r$ are connected in parallel between the resistance $R$. The maximum energy given to the resistor will be, only when
- A$R=r / 2$
- B$R=r$
- ✓$R=2 r$
- D$R=0$
✓
Answer
Correct option: C.
$R=2 r$
(c) Lowest resistance will be in the case when all the resistors are connected in parallel.$\begin{aligned}& \frac{1}{R}=\frac{1}{0.1}+\frac{1}{0.1} \ldots \ldots . . \quad 10 \text { times } \\& \frac{1}{R}=10+10 \ldots \ldots .10 \text { times } \\& \frac{1}{R}=100 \text { i.e. } R=\frac{1}{100} \Omega\end{aligned}$
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