2026 · Q112
Which combination of three resistors R1, R2 and R3 has minimum total resistance? (Consider R1 = 1 Ω, R2 = 2 Ω and R3 = 3 Ω)
general-sciencephysics-light-electricity
- AWhen all are connected in parallel
- BWhen all are connected in series
- CWhen R1 and R2 are connected in parallel and R3 is in series of them
- DWhen R1 and R3 are connected in parallel and R2 is in series of them
Explanation
Resistors in parallel give the lowest total resistance. All in parallel: 1/(1/1 + 1/2 + 1/3) = 6/11 ≈ 0.55 Ω, versus 6 Ω in series, 11/3 Ω for option C and 11/4 Ω for option D. Hence the all-parallel combination (option A) has minimum total resistance.