An electric heater consists of a nichrome coi | vedclass

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Question

(A) The power consumed by an electric heater is given by the formula $P = \frac{V^2}{R}$,where $V$ is the voltage and $R$ is the resistance of the coi

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more than $1 \,kW$

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(A) The power consumed by an electric heater is given by the formula $P = \frac{V^2}{R}$,where $V$ is the voltage and $R$ is the resistance of the coil.Given that the voltage $V = 220 \,V$ remains constant.From the formula,we see that $P \propto \frac{1}{R}$.When a part of the coil is cut off,the length of the wire decreases. Since resistance $R = \rho \frac{L}{A}$,where $L$ is the length,decreasing the length $L$ results in a decrease in resistance $R$.Since the resistance $R$ decreases,the power $P$ consumed by the heater must increase.Therefore,the new power consumed will be more than $1 \,kW$.

An electric heater consists of a nichrome coil and runs under $220 \,V$,consuming $1 \,kW$ power. Part of its coil burned out and it was reconnected after cutting off the burnt portion. The power it will consume now is

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