The heating coils rating at $220\, volt$ and producing $50\, cal/sec$ heat are available with the resistances $55\,\Omega $ , $110\,\Omega$ , $220\,\Omega $ and $440\,\Omega $. The heater of maximum power will be of............. $\Omega$
A$440$
B$220$
C$110$
D$55$
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D$55$
d $\frac{H}{t} = \frac{{{V^2}}}{R}$ $ \Rightarrow $ $\frac{H}{t} \propto \frac{1}{R}$
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