An artificial satellite in orbit around the Earth is essentially in a state of free fall. The force of gravity between the satellite and the Earth causes the satellite to accelerate towards the Earth. However, the satellite is also moving horizontally at a sufficient speed that as it falls, it is also moving forward enough to maintain a stable orbit. This means that the satellite is continuously falling towards the Earth but is also moving fast enough that it never hits the Earth`s surface.

The acceleration of the satellite towards the Earth is provided by the force of gravity. This force is proportional to the mass of the Earth and the mass of the satellite and inversely proportional to the square of the distance between them. As long as the satellite is at a sufficient height and moving at the right speed, the force of gravity will provide the necessary acceleration to keep it in orbit around the Earth.

So, in summary, it is the gravitational force of the Earth that provides the necessary acceleration for the satellite`s motion, keeping it in a stable orbit.