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(B) The power consumed by a bulb is given by the formula $P = i^2R$,where $i$ is the current and $R$ is the resistance.Since $R$ is constant,we have $

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$2$

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(B) The power consumed by a bulb is given by the formula $P = i^2R$,where $i$ is the current and $R$ is the resistance.Since $R$ is constant,we have $P \propto i^2$.Taking the derivative or using the approximation for small changes,we get $\frac{\Delta P}{P} = 2 \frac{\Delta i}{i}$.Given that the percentage change in current is $\frac{\Delta i}{i} 	imes 100 = 1\%$.Therefore,the percentage change in power is $\frac{\Delta P}{P} 	imes 100 = 2 	imes (\frac{\Delta i}{i} 	imes 100) = 2 	imes 1\% = 2\%$.Thus,the power consumed changes by $2\%$.

If the current through a bulb changes by $1\%$,what is the percentage change in the power consumed?

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