In a meter-bridge if the left and right gaps are connected with (2 ) and (3 ) resistances, respectively then the bridge is balanced. The resistance to be connected with (3 ) resistance to get the balancing point at midpoint of the bridge wire is

Step-by-step solution

Key Idea In a meter-bridge, if the balancing point is at the midpoint of the bridge wire, then it shows the resistance gaps have equal resistance. Given, ( aligned & R₁=2 & R₂=3 aligned ) and (R₂=3 ) For meter-bridge, ( R₁ R₂ = l₁ L-l₁ ) Where, (l₁ ) is balancing length, ( aligned R₁ R₂ & = l₁ l₁ ( l₁=L-l₁ ) R₁ & =R₂ 2 & =3 | x aligned ) Here, (x ) is the parallel balancing resistance to (3 ) resistor. ( aligned Hence, 3 x 3+x & =2 x & =6 aligned ) Hence, the correct option is (d).