A cylinder of radius $R$ made of a material of thermal conductivity $K_1$ is surrounded by a cylindrical shell of inner radius $R$ and outer radius $2R$ made of material of thermal conductivity $K_2.$ The two ends of the combined system are maintained at two different temperatures. There is no loss of heat across the cylindrical surface and the system is in steady state. The effective thermal conductivity of the system is
${K_1} + {K_2}$
$\frac{{{K_1}{K_2}}}{{{K_1} + {K_2}}}$
$\frac{{{K_1} + 3{K_2}}}{4}$
$\frac{{3{K_1} + {K_2}}}{4}$
A cylinder of radius $R$ made of a material of thermal conductivity$ k_1$ is surrounded by a cylindrical shell of inner radius $R$ and outer radius $2R$ made of a material of thermal conductivity $k_2$. The two ends of the combined system are maintained at different temperatures. There is no loss of heat from the cylindrical surface and the system is in steady state. The effective thermal conductivity of the system is
Two rods are connected as shown. The rods are of same length and same cross sectional area. In steady state, the temperature $\left( \theta \right)$ of the interface will be........ $^oC$
The distribution of relative intensity $I (\lambda )$ of blackbody radiation from a solid object versus the wavelength $\lambda $ is shown in the figure. If the Wien displacement law constant is $2.9 × 10^{-3}\ mK$ , what is the approximate temperature of the object ....... $K$.
A sphere and a cube of same material and same volume are heated upto same temperature and allowed to cool in the same surroundings. The ratio of the amounts of radiations emitted will be
Gravitation force is required for