1. Science Starter! Find your new seat!

2. Science Starter! Find your new seat!

4. Inertia Tendency of an object to resist a change in motion. Proportional to an object’s mass: Large mass  High Inertia  Difficult to move Small mass  Low Inertia  Easy to move

5. Newton’s First Law of Motion “Law of Inertia” “Every object continues in a state of rest, or a state of motion in a straight line at constant speed, unless acted upon by an unbalanced force.”

6. Examples Inertia Ring Newton's Bottle Egg Drop Table Cloth Chaos

7. What role do SEATBELTS play in car safety?

8. Forces Force: Push or pull (measured in Newtons [N]) Contact Forces: Forces that exist between surfaces that are touching Field Forces: Forces that exist between surfaces that are not touching

10. FTFT FgFg “Free-Body” Diagrams va = 0 m/s 2 Example: A skydiver falling at constant velocity with an open parachute (ignore air resistance)

11. Free – Body Diagrams 1. Object is drawn as a dot. 2. Force Vectors (  ): labeled and pointing in direction of force. 3. Arrows drawn starting from the dot, pointing away. * 4. Draw acceleration and velocity vectors next to diagram. Example: Free-body diagram of a sky-diver with an open parachute FTFT FgFg v a = 0 m/s 2

12. Examples 1. A ball hangs motionlessly from a cord. 2. A ball rests in the palm of a hand.