Thermal Propert...

With rise in temperature, density of a given body change according to one of the following relations 

The figure shows a system of two thin concentric spherical shells of radii $${r_1}\;{\text{and}}\;{r_2}$$ and kept at temperatures $${T_1}\;{\text{and}}\;{T_2}$$ respectively. The radial rate of heat in a substance between the two concentric spheres is proportional to :

Critical temperature of a gas obeying van der waals' equation is : 

Which of the following does not affect the distribution of insolation?

Two materials having coefficients of thermal conductivity $$'3K'$$ and $$'K'$$ and thickness 'd' and $$'3d'$$, respectively, are joined to form a slab as shown in the figure. The temperature of the outer surfaces are $$'\theta_2'$$ and $$'\theta_1'$$ respectively, $$(\theta_2 > \theta_1)$$. The temperature at the interface is?

In a Carnot engine, when heat is absorbed from the source, temperature of source 

At ordinary temperature,the molecule of an ideal gas have only translation and rotational kinetic energies. At high temperature,they may have vibrational energy.As a result of this, at higher temperature molar specific heat capacity at constant volume $$ C_v $$ for a diatomic gas is

One mole of an ideal gas passes through a process where pressure and volume obey the relation $$P = P_0 \left[1 - \dfrac{1}{2} \left(\dfrac{V_0}{V} \right)^2 \right]$$. Here $$P_0$$ and $$V_0$$ are constants . Calculate the change in the temperature of the gas if its volume change from $$V_o $$ to $$2 V_o$$.

A compound rod is formed of a steel core of diameter $$1cm$$ and outer casing is of copper, whose outer diameter is $$2 cm$$. The length of this compound rod is $$2m$$ and one end is maintained as $$100^{\circ}C$$, and the end is at $$0^{\circ}C$$. If the outer surface of the rod is thermally insulated, then heat current in the rod will be:
(Given : Thermal conductivity of steel $$= 12\ cal/m-K-s$$, thermal conductivity of copper $$= 92\ cal/m-K-s$$).

Five wires each of cross-sectional area A and length l are combined as shown in figure. The thermal conductivity of copper and steel are K1 and K2 respectively. If $$A$$ is maintained at $$100^{\circ}C$$ and $$C$$ is maintained at $$0^{\circ}C$$. The rate emitted at $$C$$ is : (assume the curve surfaces of rods are thermally insulated).