If a load of $9 \, kg$ is suspended on a wire,the increase in length is $4.5 \, mm$. The force constant of the wire is

The two thigh bones (femurs),each of cross-sectional area $10 \, cm^2$,support the upper part of a person of mass $50 \, kg$. The average pressure sustained by the femurs is ............. $N/m^2$.

Which of the following is an amorphous solid?

The reason for the change in shape of a regular body is

$A$ rod of constant cross-section moves towards the right with constant acceleration $a$. The graph of stress versus distance from the left end is shown in the figure. If the density of the material of the rod at cross-section $1$ is $9 \text{ g/cm}^3$,find the density at cross-section $2$ in $\text{g/cm}^3$.

If a solid breaks under a pressure greater than $13 \ atm$ and that solid has a specific gravity of $4$,what is the maximum height of a cylinder made from the solid that can be built at the Earth's surface (in $m$)? (Note: $1 \ atm = 10^5 \ Pa$ and take $g = 10 \ m/s^2$.)