| Priniciple 1of Gravitational Force | All objects with mass are attracted to one another by the gravitational force. |
| Principle 2 of Gravitational Force | The gravitational force between two masses is directly proportional to the mass of each object. |
| Principle 3 of Gravitational Force | The gravitational force between two masses is inversely proportional to the square of the distance between those two objects. |
| Principle 1of Centripetal Force | Circular motion requires centripetal force. |
| Principle 2 of Centripetal Force | The larger the centripetal force, the faster an object travels in a circle of a given size. |
| Principle 3 of Centripetal Force | At a given speed, the larger the centripetal force, the smaller the circle. |
| Centripetal Force | The force necessary to make an object move in a circle. It is directed perpendicular to the velocity of the object, which means it points toward the centre of the circle. |
