$A$ block of mass $0.50 \ kg$ is moving with a speed of $2.00 \ m/s$ on a smooth surface. It strikes another mass of $1.00 \ kg$ at rest and then they move together as a single body. The energy loss during the collision is ............. $J$.

$A$ 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 ............. $J$.

$A$ 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:

$A$ particle of mass $m$ moving eastward with a speed $v$ collides with another particle of the same mass moving northward with the same speed $v$. The two particles coalesce on collision. The new particle of mass $2m$ will move in the north-easterly direction with a velocity

$A$ particle of mass $m$ moving with velocity $v$ collides with a stationary particle of mass $2m$ and sticks to it. What is the combined velocity of the system?

$A$ scooter of mass $40 \ kg$ moving with a velocity of $4 \ m/s$ collides with another scooter of mass $60 \ kg$ moving with a velocity of $2 \ m/s$. After the collision,both scooters stick together. Find the loss in kinetic energy in $J$.