## Quick Reference

The following law that describes the force of attraction that exists between two particles, assumed to be isolated from all other bodies. Consider two particles *P* and *S*, with gravitational masses *m* and *M*, respectively. Let **r** be the position vector of *P* relative to *S* (that is, the vector represented by and let *r*=|**r**|. Then the force **F** experienced by *P* is given bywhere *G* is the gravitational constant. Since **r**/*r* is a unit vector, the magnitude of the gravitational force experienced by *P* is inversely proportional to the square of the distance between *S* and *P*. The force experienced by *S* is equal and opposite to that experienced by *P*.

*Subjects:*
Mathematics.

## Related content in Oxford Index

##### Reference entries

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.