When a potential difference $V$ is applied across a wire of resistance $R$, it dissipates energy at a rate $W$. If the wire is cut into two halves and these halves are connected mutually parallel across the same supply, the energy dissipation rate will become:
Solution
<p>$$\begin{aligned}
& \frac{\mathrm{v}^2}{\mathrm{R}}=\mathrm{W} \qquad \text{.... (i)}\\
& \frac{\mathrm{v}^2}{\frac{1}{2}\left(\frac{\mathrm{R}}{2}\right)}=\mathrm{W}^{\prime} \quad \text{.... (ii)}
\end{aligned}$$</p>
<p>From (i) & (ii), we get</p>
<p>$W^{\prime}=4 W$</p>
About this question
Subject: Physics · Chapter: Current Electricity · Topic: Electrical Power
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