Gravitational fields

What is a gravitational field?

A field creates around any object with mass. This extends all the way to infinity but diminishes as the distance from the centre of mass of the object increases.

What is gravitational potential?

The work done per unit mass to bring an object from infinity to a point in the gravitational field.

Why is gravitational field strength negative?

It is an attractive force that acts in the opposite direction to the displacement from the centre of mass.

How does magnitude of gravitational field strength change as the displacement from the centre of mass increases?

Decreases with the inverse square law.

What are the 4 types of orbit that a satellite can have?

Polar orbit.
Low earth orbit.
Equatorial orbit.

Geostationary orbit.

What are the features of a geostationary orbit?

In orbit around the earth’s equator.

Rotates in the same direction as the earths rotation.

Has an orbital period of 24 hours.