$A$ completely inelastic collision is one in which the two colliding particles

$A$ ball is dropped from a height of $10 \,m$. The ball embeds itself $1 \,m$ into the sand and stops. Which of the following statements is correct regarding this process?

$A$ bag of mass $M$ is suspended by a long string. $A$ bullet of mass $m$ moving with velocity $v$ hits the bag and gets embedded in it. For the (bag + bullet) system:

$A$ body of mass $20 \ kg$ moving with a speed of $10 \ m/s$ collides with a stationary body of mass $5 \ kg$. After the collision,both bodies stick together. The combined kinetic energy of the system will be $...... \ J$.

Ball $A$ of mass $1 \,kg$ moving along a straight line with a velocity of $4 \,ms^{-1}$ hits another ball $B$ of mass $3 \,kg$ which is at rest. After collision, they stick together and move with the same velocity along the same straight line. If the time of impact of the collision is $0.1 \,s$, then the force exerted on $B$ is (in $\,N$)

Two particles $A$ and $B$ of equal mass $M$ are moving with the same speed $v$ as shown in the figure. They collide completely inelastically and move as a single particle $C$. The angle $\theta$ that the path of $C$ makes with the $X$-axis is given by