ORBITAL MOTION, NATURAL AND ARTIFICIAL SATELLITES

What allows planets and satellites to maintain circular orbits

* Gravity produces the gravitational force that acts as the object’s centripetal force
* The presence of the centripetal force allows for the object to maintain its circular orbit

What type of satellite can a planet’s moon be described as

A natural satellite

Give two examples of artificial satellites

TV satellites

Satellites used for satellite imaging

Explain why for a stable orbit, the radius of orbit must change if the speed changes

* At higher speeds, the object requires a greater centripetal force
* For a greater centripetal force, the gravitational force must also increase
* This is achieved by reducing the radius of orbit

Explain how the force of gravity acting on a satellite affects its speed and velocity

* The force can alter its velocity since the direction is continually changing
* It can’t cause a change of speed since there is no force component in the direction of motion

What is a satellite

any object that orbits a celestial body (a star/planet)

What is an orbit

The curved path of one celestial object or spacecraft around another celestial object