Embibe Experts Solutions for Exercise 5: Assignment

In an experiment with a continuous flow calorimeter, an input power of $50 W$ produced a rise of $50°\mathrm{C}$ in the liquid. When the power was tripled, the same temperature rise was achieved by making the rate, of flow of liquid $n$ times its initial value. If the power lost to the surrounding in each case is $25 W$, value of $n$ is

A brass rod and an aluminium rod each of length $1 \mathrm{m}$ and same cross section area $1{ \mathrm{cm}}^2$ are placed in contact with each other as shown. Temperature of both the rods is raised by $100 K$. The coeffcients of linear expansion of brass and aluminium are $2.0\times {10}^{-5}{ \mathrm{K}}^{-1}$ and $2.4\times {10}^{-5}{ \mathrm{K}}^{-1}$ respectively. If the Young's moduli of brass and aluminium are ${10}^{11} \mathrm{N} {\mathrm{m}}^2$ and $7\times {10}^{10} \mathrm{N} {\mathrm{m}}^2$ respectively then stress in the rods is

Two metallic rods of equal length and cross-section but thermal conductivities $K_1$ and $K_2$ are welded together end to end. The resulting thermal conductivity of this resulting rod will be

A metal sphere having inner radius a and outer radius $b$ has thermal conductivity $K=\frac{K_0}{r^2}(a\le r\le b)$. The thermal resistance between inner and outer surface for radial heat flow is

The figure shows the face and interface temperature of a composite slab consisting of four materials, of identical thickness, through which the heat transfer is steady. Which material has maximum thermal conductivity?

The wavelength corresponding to maximum spectral radiancy of a black body $A$ is ${\lambda }_A=5000 \stackrel{\mathrm{o}}{\mathrm{A}}$. Consider another black body $B$ whose surface area is twice that of $A$ and total radiant energy emitted by $B$ is $16$ times that emitted by $A$. The wavelength corresponding to maximum spectral radiancy for $B$ will be

The coefficient of volume expansion for an ideal gas at constant pressure

When the temperature of a body increases from $T$ to $T+\mathrm{\Delta }T$, its moment of inertia increases from $I$ to $I+\mathrm{\Delta I}$. The coefficient of linear expansion of the body is $\alpha$. The ratio $\frac{\mathrm{\Delta I}}{I}$ is equal to