Gravitation 1.4

1.4.1    Gravitation

We know from Higher that Newton's Law of Universal Gravitation relates the gravitational force (F) between two masses to their separation in space and to the Gravitational Constant (G):           



Where:    
G is the Universal Gravitational Constant (6.67 x 10-11 Nm2kg-2)

                M is the mass of the larger body (e.g. planet)

                m is the mass of the smaller body (e.g. moon)

                r is the radius (distance) between the centres of mass.



The following simulation should help you to visualise this effect:




1.4.2    Gravitational Fields

A gravitational filed is a region, around a massive body, where a gravitational force is experienced. Gravitational field strength at any point is defined as the force per unit mass at that point (Nkg-1). As Newton's Law implies:

     so, the gravitational field strength changes as height (above the planet) increases. Thus, 

          


Activity                                        

Back to AH Lessons