A railway engine of mass 2 tons moving at a speed of 72 km `h^(-1)` collides with a wagon at rest. After collision both have a common velocity of 36 km `h^(-1)`. Find the mass of the wagon. (1 ton = 1000 kg)

A ball of mass 100g moving at a speed of 12 m s^(-1) strikes another ball of mass 200 g at rest. After the collision both the balls move with a common velocity. Find the common velocity.

Ramu saw in a NEWS channel that a goods train of mass 200 metric ton moving with a velocity of 72 km h^(-1) collides with a passenger train of mass 300 metric ton with a velocity of 54 km h^(-1) coming in the opposite direction on the same track and both the trains move together after collision. He calculates their common velocity. Find what could be his answer.

A spere of mass 20 kg moving with a velocity 40 ms^(-1) collides with another sphere of mass 15 kg which is at rest . After collision they move with the same velocity . Find the velocity .

A railway carriage of mass 9000 kg moving with a speed of 36kmh^(-1) collides with a stationary carriage of same mass. After the collision, the carriages get coupled and move together. What is their common speed after collision? What type of collision is this?

A railway carriage of mass 9000kg moving with a speed of 36kmh^(-1) collides with a stationary carriage of the same mass. After the collision, the two get coupled and move together. What is this common speed ? What type of collision is this?