There are a large number of cells available, each marked $(6 \,V , 0.5 \,\Omega)$ to be used to supply current to a device of resistance $0.75 \,\Omega$, requiring $24 \,A$ current. How should the cells be arranged, so that power is transmitted to the load using minimum number of cells?
A
Six rows, each containing four cells
B
Four rows, each containing six cells
C
Four rows, each containing four cells
D
Six rows, each containing six cells
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B
Four rows, each containing six cells
b (b)
$E=6 \,V$
$r=0.5 \,\Omega$
$R=0.75 \,\Omega$
$i=24 \,\Omega$
$S(0.5)=P(0.75)$
$2 \,s=3 p$
$i=\frac{P S E}{S r+P R}$
$24=\frac{P\left(\frac{3}{2} P\right) 6}{15 P}$
$P=4$ rows
$S=6$ cells
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