A $2\,kg$ block slides on a horizontal floor with a speed of $4\, m/s$. It strikes a  uncompressed spring, and compresses it till the block is motionless. The kinetic friction  force is $110\,N$ and spring constant is $1000\, N/m$. The spring compresses by ........ $cm$

A uniform chain of length $L$ changes partly from a table which is kept in equilibrium by friction. The maximum length that can withstand without slipping is $l$, then coefficient of friction between the table and the chain is

A body of mass $\mathrm{m}$ is kept on a rough horizontal surface (coefficient of friction $=\mu$ ) A horizontal force is applied on the body, but it does not move. The resultant of normal reaction and the frictional force acting on the object is given by $\mathrm{F},$ where $\mathrm{F}$ is

A block of mass $50 \,kg$ can slide on a rough horizontal surface. The coefficient of friction between the block and the surface is $0.6$. The least force of pull acting at an angle of $30^°$ to the upward drawn vertical which causes the block to just slide is ........ $N$

The tension $T$ in the string shown in figure is

$A$ block $P$ of mass m is placed on a frictionless horizontal surface. Another block Q of same mass is kept on $P$ and connected to the wall with the help of a spring of spring constant k as shown in the figure. ${\mu _s}$ is the coefficient of friction between$  P$ and $ Q$. The blocks move together performing SHM of amplitude $A$. The maximum value of the friction force between $P$ and $Q$ is