Answer:
Explanation:
Heat flow in a circular rod is given by
[tex]Q=\frac{kAdT}{dx}[/tex]
where Q= heat flow
k=thermal conductivity
A=area of cross-section
dT=Change in temperature
dx=change in length
Also A can be written as
[tex]A=\pi r^2[/tex]
thus Q is Proportional to
[tex]Q\propto \frac{r^2}{l}[/tex]
For option (a)
[tex]Q\propto \frac{(2r_0)^2}{2l_0}[/tex]
[tex]Q\propto \frac{2r_0^2}{l_0^2}[/tex]
(b)[tex]Q\propto \frac{(2r_0)^2}{l_0}[/tex]
[tex]Q\propto \frac{4r_0^2}{l_0}[/tex]
(c)[tex]Q\propto \frac{r_0^2}{2l_0}[/tex]
(d)[tex]Q\propto \frac{r_0^2}{l_0}[/tex]
So Rod b will conduct the most Heat
