If the current through a resistor in a circuit increases by $3 \%$, then the power dissipated by the resistor
KVPY 2013, Medium
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(b)
Power dissipated by resistor is
$P=I^2 R \Rightarrow \frac{\Delta P}{P}=\frac{2 \Delta I}{I}$
or $\frac{\Delta P}{P} \times 100=\frac{2 \Delta I}{I} \times 100$
Per cent change in power dissipation
$=2 \times$ Per cent change in current $=2 \times 3 \%=6 \%$
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