Q 12-03-105JEE MainJEE Main 2024 (30 Jan, Shift 2)Easy
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:
Answer: (D) $4W$
Each half has resistance $R/2$; in parallel they give $R/4$.
$$W' = \frac{V^2}{R/4} = 4\frac{V^2}{R} = 4W$$
Solution by Sreeraj P, M.Sc Physics