A metre bridge experiment, the resistance in the left gap is 20 and in the right gap is 60 . The bridge is balanced. The distance of the null point from the centre of the wire is

Step-by-step solution

Let l be the balancing length from the left end of the metre bridge. Using the principle of the metre bridge, R₁ R₂ = l 100 - l Substituting the given values, 20 60 = l 100 - l 1 3 = l 100 - l 100 - l = 3l 4l = 100 l = 25 cm The centre of the metre bridge wire is at 50 cm. Distance of the null point from the centre of the wire = 50 - 25 = 25 cm. Answer: 25 cm