Gravity The Forces in Creation

4 Forces of Creation 1. Gravity Attractive force between 2 objects weakest force equal strength between 2 objects from opposite directions

4 Forces of Creation 2. Electromagnetic between particles w/ electric charge can be attractive or repulsive likes repel; opposites attract

4 Forces of Creation 3. Weak Force 4. Strong Force govern radioactive processes in atoms holds the center of the atom, the nucleus, together the strongest force small range

3 Basic principles of Gravity from the Universal Law of Gravitation 1. All objects with mass are attracted to one another by the gravitational force 2. The gravitational force between 2 masses is directly proportional to the mass of each object. (If you increase the mass of 1 object, then gravitational attraction increases, too.) 3. The gravitational force between 2 masses is inversely proportional to the square of the distance between those 2 objects. If Distance big, force small. If distance small, force big.

Circular Motion Centripetal Force (Def.) force that makes an object move in a circle. It is perpendicular to the velocity of the object, toward the center of the circle Circular motion requires centripetal force The larger the centripetal force, the faster an object travels in a circle of a given size At a given speed, the larger the centripetal force, the smaller the circle.

My Solar System Lab http://phet.colorado.edu/sims/my-solar- system/my-solar-system_en.html