A ball strikes against the floor and returns with double velocity.In which type of collision is it possible?

Its not possible.

Only one where the ball fires a rocket after hitting the floor :)

In order for a ball to strike against the floor and return with double velocity, it would require an elastic collision.

An elastic collision is a type of collision where both the momentum and kinetic energy of the system are conserved. In this case, when the ball strikes the floor, it undergoes a downward velocity change due to the floor's impact. After the collision, the ball rebounds with the same magnitude of velocity but in the opposite direction. The change in velocity is twice the initial velocity, indicating that the ball's velocity has doubled.

To determine the type of collision, it is important to understand the principles of momentum and kinetic energy conservation. Momentum is conserved when the sum of the momenta of the objects before the collision is equal to the sum of the momenta after the collision. Kinetic energy conservation states that the total kinetic energy of the system before the collision is equal to the total kinetic energy after the collision.

Hence, for the ball to return with double velocity, it would require an elastic collision where both momentum and kinetic energy are conserved.