Question

Challenging simple application of math in physics.

I've encountered this problem during my study of simple circuits. The physics behind it is simple and I'll explain it below. What's curious is that the only explanation I found for it was purely a mathematical one.

Given the following circuit, asume that only the circular wire has resistance and the rest of the circuit has an electrical resistance of 0.

Knowing that you can choose to relocate points A and B explain and prove where these points should be placed so that the equivalent resistance of the circular wire is minimal/maximal

Answer 1

Now, as for the physics-what we're dealing with is a parallel resistances.

The formula for the equivalent resistance when dealing with 2 parallel resistances is:

equiv. resistance=(R1*R2)/(R1+R2)

Answer 2

Where :