$100 \,g$ of a iron ball having velocity $10 \,m/s$ collides with a wall at an angle ${30^o}$ and rebounds with the same angle. If the period of contact between the ball and wall is $0.1 \,second$, then the force experienced by the ball is …………. $\mathrm{N}$

A bullet is fired from a gun. The force on the bullet is given by $F = 600 – 2 \times {10^5}t$, where $F$ is in newtons and $t$ in seconds. The force on the bullet becomes zero as soon as it leaves the barrel. What is the average impulse imparted to the bullet  ……….. $N-s$

A body of mass $5 \,kg$ is moving with velocity of $\vec{v}=(2 i+6 \hat{j}) \,m / s$ at $t=0 \,s$. After time $t =2 \,s$, velocity of body is $(10 \hat{i}+6 \hat{j})$, then change in momentum of body is ……… $kg m / s$

A body of $2\, kg$ has an initial speed $5ms^{-1}$. A force acts on it for some time in the direction of motion. The force time graph is shown in figure. The final speed of the body.  ………. $m{s^{ – 1}}$