The n rows each containing m cells in series are joined in parall… - Vidyadip

MCQ

The $n$ rows each containing $m$ cells in series are joined in parallel. Maximum current is taken from this combination across an external resistance of $3 \Omega$ resistance. If the total number of cells used are 24 and internal resistance of each cell is $0.5 \Omega$ then

A
$m=8, n=3$
B
$m=6, n=4$
✓
$m=12, n=2$
D
$m=2, n=12$

✓

Answer

Correct option: C.

$m=12, n=2$

(c) Total cells $=m \times n=24$for maximum current in the circuit $R=\frac{m r}{n}$$\Rightarrow 3=\frac{m}{n} \times(0.5) \Rightarrow m=6 n$On solving equation (i) and (ii), we get $m=12, n=2$

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