In metre bridge experiment, the resistance in the left gap is 15 and in the right gap is 45 . The bridge is balanced. The distance of the null point from the centre of the wire is

Step-by-step solution

Let the null point be at a distance l from the left end of the metre bridge wire. Using the balancing condition of the metre bridge: R₁ R₂ = l 100 - l Substituting the given values, R₁ = 15 , and R₂ = 45 , : 15 45 = l 100 - l 1 3 = l 100 - l 100 - l = 3l 4l = 100 l = 25 cm The null point is at a distance of 25 cm from the left end. The centre of the metre bridge wire is at 50 cm . The distance of the null point from the centre of the wire is: 50 cm - 25 cm = 25 cm