Question

A thin wire of resistance $4\Omega$ is bent to form a circle. The resistance across any diameter is:

• A. $4\Omega$
• B. $2\Omega$
• C. $1\Omega$
• D. $8\Omega$

Answer 1

The correct option is C $1\Omega$

Given that the resistance of the total wire is $4\Omega$
Here, $ACB\left(2\Omega \right)$ and $ADB\left(2\Omega \right)$ are in parallel.
So, the resistance across any diameter is
$\Rightarrow \frac{1}{R}=\frac{1}{2}+\frac{1}{2}=\frac{2}{2}=1\Rightarrow R=1\Omega$