1. Gravity Reassessment Review Instructions 1.Click “Slideshow” then “From Beginning” 2.Read each slide carefully. 3.After reading takes notes from every page. 4.Organize your notes with subtitles. 5.Memorize your notes.

2. Isaac Newton Sir Isaac Newton was one of the greatest scientists and mathematicians that ever lived. Isaac Newton was the first person to hypothesize that the force that pulls an apple to the ground also pulls the moon toward Earth, keeping it in orbit.

3. Forces A force is a push or a pull. Force gives an object the energy to move, stop moving, or change direction. When you write with a pen you exert a force. When you peddle your bike, blow your nose, turn on a faucet, chew your gum, or swimming in a pool, you are exerting forces on other objects. We would never be able to move without exerting forces on things.

4. Force A force can be balanced which means objects motion will NOT change. When all forces on the object are combined the net force is 0N. An unbalanced force gives an object the energy to move, stop moving, or change direction. When all forces on this objects are combined the net force will NOT equal 0N.

5. Force of Gravity Newton was the first person to seriously study gravity Gravity is a force that attracts all objects toward each other. The force of gravity is measured in units called Newtons (N). Click Here to watch Gravity BrainPopClick Here (u.n. – harpool, p.w. - longhorns)

6. Gravity Measures Weight (not mass) Mass- is the amount of matter in an object and does not change on other planets. Weight- is the force of gravity on an object and can change on different planets due to their different gravitational pulls. The greater the mass the greater the force (weight) Weightlessness – free from the effects of gravity Watch ThisWatch This

7. Gravity The strength of gravity between two objects depends on two factors: 1. masses of the objects (If mass increases, force also increases) 2. distance between the objects (If distance increases, force decreases)

8. Gravity

9. Gravity Summary Gravity is the force that attracts all objects towards each other due to their masses. force. The greater the mass of an object, the greater the gravitational force. (the more mass it has the harder it pulls; less mass will pull less) (the more mass it has the harder it pulls; less mass will pull less) distanceless The greater the distance, the less the force (the closer it is the harder it pulls; the farther apart the weaker the pull)