Uniforme cirkelbeweging

An object moving along a circular path is said to exhibit circular motion, which can be either uniform or non-uniform. In uniform circular motion, the object moves at a constant speed.

For an orbiting satellite, the Earth's gravitational force provides the centripetal force required for circular motion.

At any instant, the linear velocity of the satellite is tangential to the circular path, such that its magnitude remains constant, but its direction varies.

Since the direction of the velocity changes, the satellite accelerates radially inwards at any instant. This acceleration is called centripetal acceleration or radial acceleration.

Dividing the force equation by m, the magnitude of the centripetal acceleration is the square of the velocity divided by the satellite's distance from the Earth's center.

As speed is equal to the orbital circumference, 2πr, divided by the period T, a relation between the centripetal acceleration and time period of the satellite is obtained.