$A$ steel rod with $Y = 2.0 \times 10^{11} \, N/m^2$ and $\alpha = 10^{-5} \, ^\circ C^{-1}$ of length $4 \, m$ and area of cross-section $10 \, cm^2$ is heated from $0^\circ C$ to $400^\circ C$ without being allowed to extend. The tension produced in the rod is $x \times 10^5 \, N$ where the value of $x$ is ....... .

$A$ metallic ring of radius $r$ and cross-sectional area $A$ is fitted into a wooden circular disc of radius $R$ $(R > r)$. If the Young's modulus of the material of the ring is $Y$, the force with which the metal ring expands is

$A$ force is applied to a steel wire '$A$',rigidly clamped at one end. As a result,the elongation in the wire is $0.2\,mm$. If the same force is applied to another steel wire '$B$' of double the length and a diameter $2.4$ times that of the wire '$A$',the elongation in the wire '$B$' will be $............\times 10^{-2}\,mm$ (wires having uniform circular cross sections).

In a tensile test on a metal bar of diameter $0.015 \ m$ and length $0.2 \ m$, the relation between the load and elongation within the proportional limit is found to be $F = 97.2 \times 10^6 (\Delta L)$, where $F$ is the load in $N$ and $\Delta L$ is the elongation in $m$. The Young's modulus of the material in $GPa$ is:

$A$ stress of $1.5 \, kg.wt/mm^2$ is applied to a wire of Young's modulus $5 \times 10^{11} \, N/m^2$. The percentage increase in its length is

If the ratio of diameters,lengths,and Young's modulus of steel and copper wires shown in the figure are $p, q$ and $s$ respectively,then the corresponding ratio of increase in their lengths would be