What is the shape of the graph of stress $\to$ strain up to the elastic limit?

The ratio of radii of two wires of same material is $2: 1$. If these wires are stretched by equal force,the ratio of stresses produced in them is .............

According to Hooke's law,force is proportional to:

Let a wire be suspended from the ceiling (rigid support) and stretched by a weight $W$ attached at its free end. The longitudinal stress at any point of cross-sectional area $A$ of the wire is:

Two blocks of masses $3 \, kg$ and $5 \, kg$ are connected by a metal wire going over a smooth pulley. The breaking stress of the metal is $\frac{24}{\pi} \times 10^{2} \, Nm^{-2}$. What is the minimum radius of the wire? (Take $g = 10 \, ms^{-2}$) (in $cm$)

Two equal and opposite forces are exerted on a bar (rod) as shown in the figure. The plane $PQ$ makes an angle $\theta$ with the cross-section $PR$ (having area $a$). Find the tensile stress on the plane $PQ$.