2GravityThe force of attraction that exists between all matter in the universe.Key word is matterMatter is the stuff you are and everything else is made ofIt takes a lot of mass for the gravity to be noticeable.Like planetary mass
3Law of GravityThe force of attraction between any two objects depends on their masses and the distances between them.The bigger the object, the more gravity it hasThe closer an object is to something the stronger the pull.
4Mass Mass is how much matter is in something. It is measured using grams and kilogramsIt is NOT the same as weight
5DistanceGravity’s force depends on how close the object is to something.As an object gets further away, the force of gravity on that object decreasesInverse square lawAs the distance increases the gravity decreases exponentiallyClass demonstration
61Gravitational force =Distance squared1G force =d2
7Weight, Mass, and Gravity Weight and Mass are not the same thing!!!The are related thoughWeight is your mass being pulled down by gravityGravity on earth pulls us down at 9.8 m/s2
8Weight, Mass, and Gravity How much matter you are made ofDoes not change depending locationIt is the same if you are on earth or in space or on the moonWeightThe relationship between mass and gravityChanges depending on locationIs different on earth and the moon and space
9In the absence of air resistance, all things will fall toward the earth at the same velocity Weight = mass x free-fall accelerationw= m g
10Find Your MassWe can find out how much mass we have by using the previous formulaW = mgWeight is in Newtons, so convert your lbs to N.Multiply lbs times 4.448Then divide by gravity
11Gravity on Earth Gravity pulls us down toward the center of the earth. At different parts of the earth there is more matter between the surface and the center.The Poles are flatter and the equator bulgesThe bulge means there is more gravity at the equatorPeople weigh more at the equator than the poles.
12Gravity & the MoonNewton observed the Moon’s motion and realized that its direction changes because of the gravitational attraction of EarthThe Moon is constantly falling toward EarthIf no gravity, the Moon would continue to move in a straight line and would not orbit EarthThe same is true of the planets and their moons, stars, and all orbiting bodies throughout the universe.