A uniform dense rod with non uniform young's modulus is hanging from ceiling under gravity. If elastic energy density at every point is same then young's modulus with $x$ will change as which of the shown graph

- A
- B
- C
- D

The load versus strain graph for four wires of the same material is shown in the figure. The thickest wire is represented by the line

The value of force constant between the applied elastic force $F$ and displacement will be

The strain-stress curves of three wires of different materials are shown in the figure. $P, Q$ and $R$ are the elastic limits of the wires. The figure shows that

A graph is shown between stress and strain for a metal. The part in which Hooke's law holds good is

The stress-strain graphs for materials $A$ and $B$ are shown in Figure

The graphs are drawn to the same scale.

$(a)$ Which of the materials has the greater Young’s modulus?

$(b)$ Which of the two is the stronger material?