Steel and copper wires of the same length are stretched by the same weight one after the other. The Young's modulus of steel and copper are $2 \times 10^{11} \, N/m^2$ and $1.2 \times 10^{11} \, N/m^2$,respectively. What is the ratio of the increase in their lengths?

The pressure to be applied to the ends of a steel cylinder to keep its length constant upon raising its temperature by $100^{\circ} C$ is (thermal expansion coefficient,$\alpha = 11 \times 10^{-6} / K$,Young's modulus $Y = 200 \text{ GPa}$)

Two exactly similar wires of steel and copper are stretched by equal forces. If the difference in their elongations is $0.5 \ cm$,find the elongation $(l)$ of each wire. Given: ${Y_s} = 2.0 \times {10^{11}} \ N/m^2$ and ${Y_c} = 1.2 \times {10^{11}} \ N/m^2$.

$A$ force of $10^3 \ N$ stretches the length of a hanging wire by $1 \ mm$. The force required to stretch a wire of the same material and length,but having four times the diameter,by $1 \ mm$ is:

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:

$A$ wire of length $2\, m$ is made from $10\, cm^3$ of copper. $A$ force $F$ is applied so that its length increases by $2\, mm$. Another wire of length $8\, m$ is made from the same volume of copper. If the same force $F$ is applied to it,its length will increase by ......... $cm$.