As shown in the figure, a particle of mass $10$ $kg$ is placed at a point $A$. When the particle is slightly displaced to its right, it starts moving and reaches the point $B$. The speed of the particle at $B$ is $x\, m / s$. (Take $\left. g =10\, m / s ^{2}\right)$ The value of $'x'$ to the nearest integer is.........

A lorry and a car moving with the same $K.E.$ are brought to rest by applying the same retarding force, then

In the given figure, the block of mass $m$ is dropped from the point ' $A$ '. The expression for kinetic energy of block when it reaches point ' $B$ ' is ................

A body is projected from ground at an angle ${\theta _1}$ with the horizontal with kinetic energy $K$. What is the potential energy of the body, when the velocity makes an angle ${\theta _2}$ with the horizontal?

A block of mass $10\, kg,$ moving in $x$ direction with a constant speed of $10\, m s^{-1}$, is subjected to a retarding force $F= 0.1\,x \,J/m$ during its travel from $x = 20 \,m $ to $30\, m$. Its final $KE$ will be ............... $\mathrm{J}$

Figure here shows the frictional force versus displacement for a particle in motion. The loss of kinetic energy in travelling over $s = 0$ to $20\, m$ will be......$J$