Q. Two conductors made of the same material are connected across a common potential difference. Conductor $A$ has twice the diameter and twice the length of conductor $B.$ The power delivered to the two conductors $P_{A}$ and $P_{B}$ respectively is such that $P_{A}/P_{B}$ equals to
A) 0.5
B) 1.0
C) 1.5
D) 2.0
Explanation
(d) $R = \rho\frac{l}{A}\ $and$\ P \propto \frac{1}{R} \Rightarrow P \propto \frac{A}{l} \Rightarrow P \propto \frac{d^{2}}{l} \Rightarrow P_{A} = 2P_{B}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.