Question

A wire has resistance $ 12\,\Omega $ . It is bent in the form of a circle. The effective resistance between the two points on any diameter of the circle is:

• A. $ 12\,\Omega $
• B. $ 24\,\Omega $
• C. $ 6\,\Omega $
• D. $ 3\,\Omega $

Answer 1

Answer: (D)

Resistance of wire is $12 \,ohm$.
Therefore, resistance of each semicircle $=6 \,ohm$
Two resistances are in parallel.
Their equivalent resistance $=\frac{6 \times 6}{6+6}=3\, ohm$