A steel wire of length $20 \mathrm{cm}$ is stretched to increase its length by $0.2 \mathrm{cm}$. Find the lateral strain in the wire if the Poisson's ratio for steel is $0.19$.

A steel wire of length$4.7 \mathrm{m}$ and cross-sectional area $3.0\times {10}^{-5} {\mathrm{m}}^2$ stretches by the same amount as a copper
wire of length$3.5 \mathrm{m}$ and cross-sectional area of $4.0\times {10}^{-5 } {\mathrm{m}}^2$ under a given load. What is the ratio of
the Young’s modulus of steel to that of copper?

The figure below shows the strain-stress curve for a given material. What is Young’s modulus for the given material?
 

Figure below shows the strain-stress curve for a given material. What is approximate yield strength for this material?

Two wires of diameter $0.25 \mathrm{cm}$, one made of steel and the other made of brass are loaded as shown in the figure. The unloaded length of steel wire is $1.5 \mathrm{m}$ and that of brass wire is $1.0 \mathrm{m}$. Compute the elongations of the steel and the brass wires.