Question

Two diagonally opposite comers of a square made of four thin rods of the same material, same dimensions are at temperature${40}^{o}C$ and ${10}^{o}C$. If only heat conduction takes place, then the temperature difference between the other two corners will be:

• A. $0^{o}C$
• B. ${10}^{o}C$
• C. ${25}^{o}C$
• D. ${15}^{o}C$

Answer 1

The correct option is D ${15}^{o}C$

energy flow rate is $\frac{dQ}{dt}=\frac{KA(T_1-T_2)}{L}$

let T be the temperature of the other diagonal of the square.

The rate of flow of heat from one rode is equal to another rod.

$\frac{KA({40}^0-T)}{L}=\frac{KA(T-{10}^0)}{L}$

$2T=30$

$T={15}^0$

hence D is the correct option.