Heat transfer through the walls of a cylinder of inner and outer radii r₁ and r₂, respectively is inversely proportional to

Question

Question

This question was previously asked in

BPSC AE Paper 5 (Mechanical) 2019 Official Paper

Answer 1

Concept:

We have, heat conduction through the cylindrical wall is,

\(Q=\frac{2\pi kL(\Delta T)}{ln(\frac{r_2}{r_1})}\)

where, k = Thermal conductivity, L = length of the cylinder

From the above equation,

\(Q\propto \frac{1}{ln(\frac{r_2}{r_1})}\)

Hence, heat conduction is inversely proportional to \(\ln \left( {\frac{{{r_2}}}{{{r_1}}}} \right)\)