(Solved): 2. Conductance of a cylindrical shell. Consider a cylindrical wall with inner radius \( r_{1} \), ...

2. Conductance of a cylindrical shell. Consider a cylindrical wall with inner radius \( r_{1} \), outer radius \( r_{2} \). The temperature for the inner and outer surfaces are \( T_{1} \) and \( T_{2} \) respectively. Hence the heat flow is along the radial direction. Find the thermal conductance of the cylindrical shell, assuming the length of the cylinder is \( L \) and thermal conductivity is \( k \).