When a spiral spring is stretched by suspending a load on it,the strain produced is called

The breaking stress of a wire depends upon

Which one of the following quantities does not have the unit of force per unit area?

Give an example of pure shear.

Why do rail tracks have an '$I$-shaped' girder?

The elastic behaviour of a material for linear stress and linear strain is shown in the figure. The energy density for a linear strain of $5 \times 10^{-4}$ is $\dots \; kJ/m^3$. Assume that the material is elastic up to the linear strain of $5 \times 10^{-4}$.