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# Newton's Law of Univ. Gravitation sans units

Over 300 years ago Newton figured out the Law of Universal Gravitation. The law is diagrammed below. The table describes the parts of the relationship. Note that 'G' is a *very small* number. Notice also that the gravitational force is a mutual force - felt equally by both objects.

Name | Description | Units |
---|---|---|

F_{1} |
Gravitational force felt by object 1 | Newtons |

F_{2} |
Gravitational force felt by object 2 | Newtons |

G | Gravitational constant | 6.674×10^{-11} N m^{2} kg^{-2} |

m_{1} |
Object 1 | kilograms |

m_{2} |
Object 2 | kilograms |

r | radius | meters |

## Directions

We will simplify our look at gravity to the point of error by removing all reference to the units and by deleting the gravitational constant 'G'. We will look at just the numbers, which is so very wrong! Please don't tell anyone. The formula is simplified to: **F = mass / r ^{2}**. For the problems below, find the gravitational force.

mass | distance | F = mass / r^{2} |
Effect on Gravitational Force |
---|---|---|---|

1 | 1 | 1 / 1^{2} = 1 N |
With the beginning mass the gravitational force is 1 N |

2 | 1 | ______ times the mass = ______ times the gravitational force | |

3 | 1 | ______ times the mass = ______ times the gravitational force | |

4 | 1 | ______ times the mass = ______ times the gravitational force | |

16 | 1 | 16 / 1^{2} = 16 N |
With the beginning distance the gravitational force is 16 N |

16 | 2 | _____ times the distance = ______ the gravitational force | |

16 | 3 | _____ times the distance = ______ the gravitational force | |

16 | 4 | _____ times the distance = ______ the gravitational force |