Question

What is the advantage of using thick metallic strips of join wires in a potentiometer?

Answer 1

As the area of cross-section of metallic strips in potentiometer is larger than a single wire thus it introduces the least resistance while joining the wires. This is also known as contact resistance.

The metal strips have low resistance and need not be counted in the potentiometer length $l$ of the null point. One measures only their lengths along the straight segments (of length $l$ metre each). This is easily done with the help of centimeter or meter rulers and leads to accurate measurements.