3. Newton Isaac Newton was an English Scientist In 1667, he developed 3 laws of motion that described movement of objects in terms of forces These laws of motion still hold true today

4. Newton Isaac Newton was an English Scientist In 1667, he developed 3 laws of motion that described movement of objects in terms of forces These laws of motion still hold true today

5. FORCE = Any push or pull which causes something to move or change its speed or direction What is a Force?

6. Forces can be BALANCED or UNBALANCED Balanced forces are equal in size and opposite in direction Unbalanced forces are not equal in size and/or opposite in direction. If the forces on an object are UNBALANCED, we say a NET force results. What is a Force?

7. What is Friction? Friction = A force that opposes or slows down motion Caused by the physical contact between moving surfaces The amount of friction depends upon the kinds of surfaces and the force pressing the surfaces together Changes motion into heat

8. First Law : An object at rest stays at rest or an object in motion, stays in motion (in the same direction/at the same speed) unless acted upon by an unbalanced force Also called the law of inertia

9. Inertia The tendency of an object to resist any change in its motion The greater the mass the greater the inertia The greater the speed the greater the inertia

10. Examples of Newton’s 1 st Law a)car suddenly stops and you strain against the seat belt b) when riding a horse, the horse suddenly stops and you fly over its head c) the magician pulls the tablecloth out from under a table full of dishes d) the difficulty of pushing a dead car

12. Discussion Questions 1.What are the differences in how balanced and unbalanced forces affect motion? 2.What is inertia? How is it involved in Newton’s 1 st Law of Motion? 3.Two children who are fighting over a toy pull on it from opposite sides. The result is a standoff. Explain this in terms of the net force.

13. Tricky Tricks 1.Fill a beaker with water. 2.Cover the beaker with an index card 3.Place a penny in the center of the card 4.Hold the base of the cup with it resting on the table 5.Use your index finger to flick the card. QUESTIONS 1.How does this activity relate to the “pull the tablecloth” trick used by magicians? 2. Explain your observations using the vocabulary word inertia?