# Can the kinetic energy of the system be increased without applying any external force on the...

## Question:

Can the kinetic energy of the system be increased without applying any external force on the system? If yes explain how come internal force does work?

## Gravitational Force:

The gravitational force is a force between two bodies placed at a certain distance. It depends on the mass of the objects involved and the distance between them. It is the naturally occurring weakest force and always acts on the center of the distance between two bodies.

Yes, the kinetic energy of the system can be increased without applying any external force on the system.

When we throw a ball in a vertically upward direction, the ball will encounter two energies.First, the potential energy and the second is kinetic energy, When the ball leaves the hand, the velocity of the ball decrease with the increase in height, decreasing the K.E after attaining the peak height this K.E is turned into P.E.Now when the ball is dropping, this P.E is turned into K.E, and the velocity will increase with a decrease in height as the velocity increases, the K.E also increases without applying any external forces.The gravity and gravitational force work here as an internal force, due to the gravitational force the velocity increase because the gravitational force is inversely proportional to the square of the distance between two bodies here the first body is a ball and the second body is earth.

From the above example, we can say that the kinetic energy of the system can be increased without applying any external force on the system.