Question

a wire of resistance 12 ohm is bent in the form of circle?what is the effective resistance between the ends of diameter AB

Answer 1

Answer:

Explanation:

if the total resistance of the wire is R, then after bending the total resistance will still be R.

Now, along any diameter, we can say that the whole circle is divided into two segments.

So, the resistance of each segment is half, i.e. R/2

Now, these two segments are connected in parallel. So, the effective resistance is

1/R=1/(R/2)+1/(R/2)= 2/R+2/R= 4/R

therefore, R/4=12/4 = 3 ohm