2026 · Q51
Three resistors R1, R2 and R3 (R1 > R2 > R3) are connected to a battery of voltage V such that the circuit generates maximum heat per unit time. Which one among the following is the correct circuit combination for this?
General KnowledgePhysics
- AR1, R2 and R3 are connected in series combination
- BR1, R2 and R3 are connected in parallel combination
- CR1 and R3 are connected in parallel and R2 is connected in series to the combination
- DR1 and R3 are connected in series and R2 is connected parallel to the combination
Explanation
Heat generated per unit time is electric power P = V^2/R. For a fixed battery voltage V, power is maximised by minimising the equivalent resistance R. The parallel combination gives the lowest equivalent resistance (lower than the smallest individual resistor), so maximum heat is generated when R1, R2 and R3 are all in parallel. The answer is (B).