If the side of a cube decreases by $1\%$,the volume strain is ........ $\%$.

Hooke's law is applicable for ....

The length of an elastic string is $a$ metres when the longitudinal tension is $4 \ N$ and $b$ metres when the longitudinal tension is $5 \ N$. The length of the string in metres when the longitudinal tension is $9 \ N$ is

The pointer reading versus load graph for a spring balance is as given in the figure. The spring constant is ........ $kg/cm$.

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 $g = 10 \ m/s^2$.)

Two identical solid balls,one of ivory and the other of wet-clay,are dropped from the same height on the floor. Which one will rise to a greater height after striking the floor and why?