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

$A$ particle of mass $m$ moving with velocity $v$ collides with a stationary particle of mass $2m$. After collision,they stick together and continue to move together with velocity ........

$A$ body of mass $20 \ kg$ moving with a velocity of $10 \ m/s$ collides with a stationary body of mass $5 \ kg$ and sticks to it. The combined kinetic energy of the system after the collision is . . . . . . $J$.

$A$ metal ball of mass $2 \,kg$ moving with a velocity of $36 \,km/h$ has a head-on collision with a stationary ball of mass $3 \,kg$. If after the collision,the two balls move together,the loss in kinetic energy due to the collision is ........ $J$.

$A$ body of mass $40\,kg$ having velocity $4\,m/s$ collides with another body of mass $60\,kg$ having velocity $2\,m/s$. If the collision is perfectly inelastic, then the loss in kinetic energy will be .............. $J$.

$A$ mass of $20\, kg$ moving with a speed of $10\, m/s$ collides with another stationary mass of $5\, kg$. As a result of the collision,the two masses stick together. The kinetic energy of the composite mass will be ............. $J$.