Question

Q13 Two metallic wires A and B are connected in parallel. Wire A has length l and radius r, wire B has a length 21 and radius 2r. Compute the ratio of the total resistance
of parallel combination and the resistance of wire A.

​Also if the wires are connected in series compute the ratio of the series combination and resistance of wire A ?

Answer 1

$$\begin{gathered} Dearstudent, \\ resis\tan ceinparallel. \\ \frac{1}{R_p}=\frac{1}{r}+\frac{1}{2r} \\ {R}_p=\frac{2r}{3} \\ ratiowillbe,\frac{\frac{2r}{3}}{r}=\frac{2}{3} \\ resis\tan ceinseries=r+2r=3r \\ ratiowillbe,\frac{3r}{r}=3 \\ Regards \end{gathered}$$