2. Do Now Explain the term work.

3. Objective Students will be able to analyze and integrate information in order to determine when work is being done on an object.

4. Agenda Do Now Expectations Computer Activity

5. Expectations Two worksheets to be completed Follow the directions and read or go to the website to complete the questions Do not go on other sites. You will also receive a zero if you are not following the expectations or rules of the classroom.

7. Do Now What are the two things needed for work to be done?

8. Objective Students will be able to analyze and integrate information in order to describe work.

9. Agenda Do Now Work and Machines Lab/Section Review

10. Work Work is when a force causes an object to move in the direction of the force

11. Energy Kinetic energy – energy that is moving  Energy is transferred when work is being done

12. Force and Work You can use force, but haven’t done any work  Pushing a car

13. Force and Motion in the Same Direction For work to be done on an object, the object must move in the same direction as the force  Work is done if 2 things happen:  The object moves as a force is applied  The direction of the object’s motion is the same as the direction of the force

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18. Calculating Work Unit used to express work is N x m, or joule (J).

19. Power and Calculating Power Power – the rate at which energy is transferred Calculating Power  Units expressed for power is (J/s), or watt (W)

20. d

21. Section Review Page 99, #1-9

23. Do Now What are some simple machines that you use in daily life?

24. Objective Students will be able to analyze and integrate information in order to explain simple machines.

25. Agenda Do Now Review Video

29. Do Now If you are putting down a bag of groceries, are you doing work? Explain.

30. Objective Students will be able to utilize information on work in order to explain whether work is being done through a spring scale lab.

31. Agenda Do Now Practice calculating work/power Expectations Spring Scale Lab

32. Calculating Work Unit used to express work is N x m, or joule (J).

33. Practice Renatta Gass is out with her friends. Misfortune occurs and Renatta and her friends find themselves getting a work out. They apply a cumulative force of 1080 N to push the car 218 m to the nearest fuel station. Determine the work done on the car.

35. Practice If 68 Joules of work were necessary to move a 4 Newton crate, how far was the crate moved?

37. Power and Calculating Power Power – the rate at which energy is transferred Calculating Power  Units expressed for power is (J/s), or watt (W)

38. Practice When doing a chin-up, a physics student lifts her 411.6 N body a distance of 0.25 meters in 2 seconds. What is the power delivered by the student's biceps?

40. Practice A person weighing 600 N gets on an elevator. The elevator lifts the person 6 m in 10 seconds. How much power was used?

42. Practice How much time is needed to produce 720 Joules of work if 90 watts of power is used?

44. Expectations Stay within your group, you should not be walking around to other groups Do not play with the materials for the experiment Keep noise level down

45. Spring Scale Lab Due at the end of the class Use loose-leaf paper Complete your OWN set of data and answers Be sure to include your name, date and section Lab Grade = Quiz Grade = 25% of your grade

46. Spring Scale Lab Open to Page 96 of textbook Use the Power formula to calculate how much power was used (time it).

47. Spring Scale Lab Once finished with the textbook, use the packet and turn to the page where it says, “Explore It!” Complete “Explore It! #1 and #3” Use the Power formula to find how much power was used (use time!)

49. Do Now Why do we use machines?

50. Objective Students will be able to analyze and integrate information in order to explain how a machine makes life easier.

51. Agenda Do Now Test Monday Directed Reading

52. Spring Scale Lab Open to Page 96 of textbook Use the Power formula to calculate how much power was used (time it).

53. Spring Scale Lab Once finished with the textbook, use the packet and turn to the page where it says, “Explore It!” Complete “Explore It! #1 and #3” Use the Power formula to find how much power was used (use time!)

55. Do Now Give an example of a simple machine and how it makes our life easier.

56. Objective Students be able to analyze and integrate information on the wheel and axel, inclined planes and screws in order to identify and give examples of how machines are used in real life situations.

57. Agenda Do Now Machines Foldable

58. Types of Machines Levers  Simple machine that has a bar that pivots at a fixed point  This fixed point is called the fulcrum  The load  Input force  3 Types of levers

59. Types of Machines - Levers First class  Fulcrum is between the input force and the load  Always change the direction of the input force  Used to increase force or to increase distance

60. Types of Machines - Levers Second Class  The load is between the fulcrum and the input force  Does not change the direction of the input force  Allows you to apply less force than the force exerted by the load

61. Types of Machines - Levers Third Class  Input force is between the fulcrum and the load  Do not change direction of the input force  Do not increase input force, meaning the output force is always less than the input force

62. Types of Machines - Guess d

63. Types of Machines

64. Types of Machines - Guess

65. Types of Machines

66. Types of Machines - Guess

67. Types of Machines

69. Do Now What are the three types of levers and how are they different from one another?

70. Objective Students will be able to analyze and integrate information on the wheel and axle, inclined planes and screws in order to identify and give examples of how machines are used in real life situations.

71. Agenda Do Now Types of Machines Foldable Section Review

72. Types of Machines - Pulleys A simple machine that has a grooved wheel that holds a rope or a cable. A load is attached to one end of the rope, and an input force is applied to the other end

73. Types of Machines - Pulleys Fixed Pulley – attached to something that doesn’t move  Pull down on rope to lift the load up  Pulley changes the direction of the force  Ex. Elevator

74. Types of Machines - Pulleys Movable Pulleys – Attached to the object being moved  Does not change a force’s direction  Increase force, but also increase the distance over which the input force must be exerted

75. Types of Machines - Pulleys Block and Tackles – When a fixed pulley and a movable pulley are used together  Mechanical advantage of a block and tackles depends on the number of rope segments

76. Types of Machines – Wheel and Axle Consists of two circular objects of different sizes; the whell is the larger of the two circular objects  Ex. Doorknobs, wrenches, and steering wheels

77. Types of Machines – Wheel and Axle Mechanical Advantage  Found by dividing the radius of the wheel by the radius of the axle  Turning the wheel results in a MA greater than 1 because the wheel of the radius of the wheel is larger than the radius of the axle

78. Types of Machines – Wheel and Axle

79. Types of Machines – Inclined Planes A straight, slanted surface  Requires smaller input force than is needed to lift the piano into the truck Mechanical Advantage  MA of an inclined plane can be calculated by dividing the length by the height to which the load is lifted

80. Types of Machines – Inclined Planes Wedges – made up of two inclined planes and that moves; often used for cutting  Ex. Doorstops, chisels, scissors MA  The longer and thinner the wedge is, the greater its MA  Less input force is required  Calculated by dividing the length of the wedge by its greatest thickness

81. Types of Machines – Inclined Planes Screws – consists of an inclined plane wrapped around a cylinder  When turned, a small force is applied over the long distance along the inclined plane  Screw applies a large force through the short distance it is pushed MA of Screws  Longer the spiral on the screw and closer the threads/pitches are, the greater its MA

82. Types of Machines – Compound Machines Machine made up of more than one simple machine  Ex. Block and tackle (two or more pulleys)  Ex. Can opener (2 nd class lever, wheel and axle, and a wedge)

83. Types of Machines – Compound Machines Mechanical Efficiency  Low in most compound machines  Compound machines have more moving parts than simple machines do, thus, more friction to overcome

84. Types of Machines – Compound Machines Important to reduce friction  Can damage the simple machines that make up the compound machine  Use lubricants to reduce friction