1. Text P409-413

2. Mass and Inertia The universe consists of matter in motion The universe consists of matter in motion

3. The greater the mass the harder it is to move. And... the harder it is to stop moving. The greater the mass the harder it is to move. And... the harder it is to stop moving.

4. Lower mass objects are easier to move...and to stop moving.

5. NEWTON’s Laws 1st Law of Motion : NEWTON’s Laws 1st Law of Motion : An object remains at a in a,until a net force acts on it. An object remains at a in a,until a net force acts on it. constant speed straight path constant speed straight path

6. An object will remain at a constant speed (unless disturbed). NEWTON’s 1st Law of Motion is the law of

7. Higher mass higher momentum Higher velocity higher momentum Momentum = mass x velocity

8. includes velocity. So, it has direction. Momentum points in the direction of motion.

9. Conservation of momentum When objects collide, all of the momentum goes somewhere.

10. Conservation of momentum When objects collide, all of the momentum goes somewhere.

11. Conservation of momentum When objects collide, all of the momentum goes somewhere.

12. Conservation of momentum When objects collide, all of the momentum goes somewhere.

13. NEWTON’s 2 nd Law of Motion : An object that has a force acting on it will change its speed (accelerate).

14. Net force is the total amount of Force (minus the forces that cancel each other out). Force of gravity Force of muscles Net force

15. When the net force is Zero. -> NO movement When the net force is NOT Zero. -> movement When the net force is Zero. -> NO movement When the net force is NOT Zero. -> movement

16. 2 Kg ? Static Equilibrium Balanced forces When all forces are balanced. The net force is Zero. There is NO movement. Static Equilibrium Balanced forces When all forces are balanced. The net force is Zero. There is NO movement. 3 Kg

17. 50 N 100 N 50 N

18. NEWTON’s 3rd Law of Motion: For every action there is an equal and opposite reaction.

19. NEWTON’s 3rd Law of Motion: For every action, there is an equal and opposite reaction.

20. NEWTON’s 3rd Law of Motion: For every action, there is an equal and opposite reaction.

22. Balanced or unbalanced? Action Reaction Gravity Inertia Friction

23. A car is traveling down a hill. Which of the following will affect the amount of energy the car has? how long the car is the time of day how much the car weighs the color of the car

24. Friction the resistive force that occurs when two surfaces travel past each other. causes physical deformation generates heat

25. Friction the resistive force that occurs when two surfaces contact each other.

26. Oliver the dog doesn't want to walk in the rain. He can make his owner pull harder on the leash to get him out the door by sitting on the vinyl floor. sitting on the tile floor. sitting on the carpeted floor. sitting on the wood floor.

27. terminal velocity gravity will accelerate an object until air resistance (friction) does not allow it to go any faster.

28. In the absence of air resistance, which of these objects will fall at the fastest rate when dropped? the ball with a mass of 75 kg the ball with a mass of 25 kg the ball with a mass of 10 kg They all fall at the same rate.

29. Gravitational force

30. Gravitational force

31. Gravitational force o Io INCREASES with Mass o DECREASES with Distance

32. All objects in the universe are attracted to each other by the force of effort. friction. gravity. inertia.

33. THE END Do Q 1-7, P413

34. Four pairs of objects have the masses shown below. If the objects in each pair are the same distance apart, the gravitational force between the objects in which pair is greatest? 1 kilogram and 1 kilogram 1 kilogram and 2 kilograms 2 kilograms and 1 kilogram 2 kilograms and 2 kilograms Four pairs of objects have the masses shown below. If the objects in each pair are the same distance apart, the gravitational force between the objects in which pair is greatest? 1 kilogram and 1 kilogram 1 kilogram and 2 kilograms 2 kilograms and 1 kilogram 2 kilograms and 2 kilograms

35. Simple Machines and work Lever Inclined plane Pulley Wedge Screw Wheel and axle Simple Machines and work Lever Inclined plane Pulley Wedge Screw Wheel and axle

36. Simple Machines Pulley Wheel & Axle Lever Inclined plane Screw Wedge Gear

38. Simple Machines Pulley Wheel & Axle Lever Pulley Wheel & Axle Lever Inclined plane Screw Wedge Gear Inclined plane Screw Wedge Gear

39. Which activity involves the use of a simple machine? riding on a seesaw flying a kite listening to a radio skiing down a hill

41. Simple Machine A mechanism that lowers the amount of force needed to do work, by increasing the distance.

42. On which simple machine is a fulcrum found? pulley wheel axle lever

43. Which of the following is often used as a lever? file nail saw crowbar

44. The Wedge The Wedge

45. The bottom of this light bulb is an example of what type of simple machine? a lever a pulley a screw a wedge

46. What type of simple machine is used to split things apart? screw wheel and axle wedge inclined plane

47. What type of simple machine is used to pull a flag up to the top of a flagpole? screw wheel and axle inclined plane pulley

48. Centripetal force The inward force on a spinning object, that stops it from going in a straight line. Perpendicular

49. Centripetal force

50. The inward force on a Spinning object. Centripetal force The inward force on a Spinning object.

51. Centripetal force The inward force on a Spinning object. Centripetal force The inward force on a Spinning object.

52. Satellites stay in place as they orbit because of... the repeated firing of rocket boosters. the gravitational pull of Earth. a narrow path through the vacuum of space. solar panels generating energy to hold them in place