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This power point is modified from the Universal Gravitation power point found at: http://www3.science.tamu.edu/CMSE/powerpoint/ on 1/5/10. What is gravity ?. Galileo and Newton gave the name gravity to the force that exists between the Earth and objects.
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This power point is modified from the Universal Gravitation power point found at: http://www3.science.tamu.edu/CMSE/powerpoint/ on 1/5/10
What is gravity? Galileo and Newton gave the name gravity to the force that exists between the Earth and objects. Newton showed that the same force exists between all objects. He even realized that it is gravity that keeps the moon in orbit!! Even today, no one knows for sure why objects attract each other.
In 1666, Isaac Newton determined that the same force that kept the planets in motion must also exist between every object. He stated that every object in the universe attracts every other object in the universe. The force of attraction between two objects is directly proportional to the product of their masses, and inversely proportional to the square of their separation distance.
So, for example, if you double the mass of one of the objects you will double the force of attraction Or If you half the mass of oneobjects You will half the force of attraction Also, for example, if you increase the distance between the objects by double (22=4) you decrease the force of attraction to ¼ of what it was. Or If you decreasethe distance ( ¼=½2) between the objects by half you will increase the attraction by four times what it was.
In equation form: m1 m2 = F G r2 F is the force of attraction, measured in NEWTONS, between masses m1 and m2 G is the Universal Gravitation Constant, equal to 6.67 x 10-11 N m2/kg2 m1 and m2 are the attracting masses, measured in KILOGRAMS r is the distance between their centers of mass, and is measured in METERS
TIDES When two large objects exert gravitational forces on each other, the force on the near side is larger than the force on the far side, because the near side is closer to the other object. This difference in gravitational force across an object due to its size is called a tidal force.
Second high tide (smaller then the other) because this side is pulled the least Gravity of moon Moon’s pull is greatest here because it is closer. Highest tide
Tidal locking This is what allows only one side of the moon to face the Earth It can even keep moons from forming!