JEE Main 2024 Physics question
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: (B)
Solution
Initially W = V²/R. After cutting, each half has R/2 and the two in parallel give R/4, so W′ = V²/(R/4) = 4W.