### How do magnets illustrate what is going on in the greater universe?

Newton developed a number of fundamental physics laws including the universal law of gravity. According to this law, the force of attraction between two objects in space depends on their masses, the distance between them, and the gravitational constant. Thus, the formula is as follows:

F_{G} = G((M_{1}M_{2})/R^{2}) where G = 6.67 x 10^{-11}.

The force of gravitation can be compared to magnets on a refrigerator. When you put a magnet closer to the refrigerator, the magnetic force becomes stronger. The opposite happens when you put it farther.

### Creative Applications

1. Why is it that magnets have to be close to the refrigerator in order to stick to it?

2. How does the gravitation constant come into play with magnets?

3. Compare the attraction between two magnets of different masses on your own refrigerator with the same distance. Are there any differences?

4. Now place one magnet much farther away from the refrigerator. Note any differences.