A rod of length $L$ with sides fully insulated is of a material whose thermal conductivity varies with $\alpha$ temperature as $ K= \frac{\alpha }{T}$, where $\alpha$ is a constant. The ends of the rod are kept at temperature $T_1$ and $T_2$. The temperature $T$ at $x,$ where $x$ is the distance from the end whose temperature is $T_1$ is
${T_1}{\left( {\frac{{{T_2}}}{{{T_1}}}} \right)^{\frac{x}{L}}}$
$\frac{x}{L}\ln \frac{{{T_2}}}{{{T_1}}}$
${T_1}{e^{\frac{{{T_2}x}}{{{T_1}L}}}}$
${T_1} + \frac{{{T_2} - {T_1}}}{L}x$
Aring consisting of two parts $ADB$ and $ACB$ of same conductivity $k$ carries an amount of heat $H$. The $ADB$ part is now replaced with another metal keeping the temperatures $T_1$ and $T_2$ constant. The heat carried increases to $2H$. What $ACB$ should be the conductivity of the new$ADB$ part? Given $\frac{{ACB}}{{ADB}}= 3$
The ratio of thermal conductivity of two rods of different material is $5 : 4$ . The two rods of same area of cross-section and same thermal resistance will have the lengths in the ratio
A thin paper cup filled with water does not catch fire when placed over a flame. This is because
When two ends of a rod wrapped with cotton are maintained at different temperatures and after some time every point of the rod attains a constant temperature, then
Under steady state, the temperature of a body