In an experiment on metre bridge, if the balancing length AC is 'x' . What would be its value, when the radius of the metre bridge wire AB is doubled? Justjfy the answer.
Consider the figure below.
here AC =x and the resistance of segments AC and BC are RAC and RBC respectively.
Now, the condition of no deflection dictates that
R/r = RAC/RBC
If the resistance of AB is doubled, the ratio R/r or RAC/RBC will remain unchanged.
Thus, the balancing length AC= x will stay the same.