Question

A wire of resistance 20 $\Omega$ is bent in the form of a circle. Find the equivalent resistance between two diametrically opposite ends.

• A. 40 Ω
• B. 20 Ω
• C. 10 Ω
• D. 5 Ω

Answer 1

The correct option is D

5 Ω

The upper semicircle will be 10 $\Omega$ and the bottom will be 10 $\Omega$. Now, these two are in parallel to each other. So, the net resistance we get as

$\frac{1}{R_{net}}$ = $\frac{1}{10}$ + $\frac{1}{10}$

$R_{net}$ = 5 $\Omega$