JEE Main202622 January 2026Morning ShiftPhysicsCurrent ElectricityActual
A meter bridge with two resistances R₁ and R₂ as shown in figure was balanced (null point) at 40 cm from the point P . The null point changed to 50 cm from the point P , when 16 resistance is connected in parallel to R₂ . The values of resistances R₁ and R₂ are _ _ _ _ .
Options
- AR₂=4 , R₁= 4 3
- BR₂=16 , R₁= 16 3
- CR₂=12 , R₁= 12 3
- DR₂=8 , R₁= 16 3
Correct answer
D. R₂=8 , R₁= 16 3
Step-by-step solution
Initial balance at 40 cm: R₁ R₂ = 40 60 = 2 3 ...(i) With 16 , parallel to R₂ , null point at 50 cm: R₁ 16R₂ 16+R₂ = 50 50 = 1 R₁ = 16R₂ 16+R₂ ...(ii) From (i): R₁ = 2 3 R₂ . Substituting in (ii): 2 3 R₂ = 16R₂ 16+R₂ . 2 3 = 16 16+R₂ 2(16+R₂) = 48 R₂ = 8 , . R₁ = 16 3 , .