Q. A wire is broken in four equal parts. A packet is formed by keeping the four wires together. The resistance of the packet in comparison to the resistance of the wire will be
A) Equal
B) One fourth
C) One eight
D) $\frac{1}{16}th$
Explanation
(d) Let the resistance of the wire be $R,$ then we know that resistance is proportional to the length of the wire. So each of the four wires will have $R/4$ resistance and they are connected in parallel. So the effective resistance will be
$\frac{1}{R_{1}} = \left( \frac{4}{R} \right)4 \Rightarrow R_{1} = \frac{R}{16}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.