Simple Machines
Objectives Explain   how machines make work  easier Calculate Mechanical Advantage of a  machine Calculate Efficiency o...
Key Words Simple           Screw  Machines                   Lever Inclined Plane                   Fulcrum Wedge
What is a Simple Machine?A  simple machine  has few or no  moving parts. Simple machines  make work easier
3 types of simple machines The inclined plane The Wedge The Screw
What is an inclined plane?A  sloped surface An inclined plane allows you to exert  your input force over a longer distan...
Inclined Planes An inclined plane is  a flat surface that is  higher on one end Inclined planes  make the work of  movin...
Increase Force             Increase distance When  the output            When   the output force is greater             ...
What is efficiency? Output   Work / Input work x 100%
EFFICIENCY Theefficiency of a machine compares output work to input work    Output Work                          100    I...
Inclined Planes   How do Inclined Planes work?
WedgesCan your teeth be machines?
Wedges Two inclined planes joined  back to back. Wedges are used to split  things.
Ideal Mechanical AdvantageInclined Plane        Wedge Divide the length    Length  of the plane of the incline by      d...
ScrewsA   screw is an  inclined plane  wrapped around a  shaft or cylinder. The inclined plane  allows the screw to  mov...
Mechanical Advantage ofScrew length of thread around the screw by the height of the screw
LEVERS
Objectives How are levers classified
What is a Lever?A  lever is a rigid bar that is free to pivot, or rotate on a fixed pointThe fixed point that the lever ...
Levers-First Class In a first class lever  the fulcrum is in the  middle and the load  and effort is on  either side Thi...
Levers-Second Class In   a second class    lever the fulcrum    is at the end, with    the load in the    middle   Think...
Levers-Third Class In a third class lever  the fulcrum is again  at the end, but the  effort is in the  middle Think of ...
Ideal Mechanical Advantage IdealMechanical Advantage =  Distance from fulcrum to the input                 force  Distanc...
Putting Machines Together
Key Words Pulley Wheeland Axle Compound Machine
Ideal Mechanical Advantage Ideal   Mechanical Advantage =              Radius of Wheel               Radius of Axle
Compound Machines Howdo Compound Machines work?  Withina compound Machine, the  output force of one simple machine  beco...
Wheels and Axles The wheel and axle  are a simple  machine The axle is a rod  that goes through  the wheel which  allows...
PulleysA    Pulley is a simple    machine made of a    grooved wheel with a    rope or cable wrapped    around it.   (A ...
Simple Machines   Simple Machines    can be put together    in different ways to    make complex    machinery
Give examples for each classof lever Hwpage: 99-101
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  • Pulley are wheels and axles with a groove around the outside.
  • Machines

    1. 1. Simple Machines
    2. 2. Objectives Explain how machines make work easier Calculate Mechanical Advantage of a machine Calculate Efficiency of a machine
    3. 3. Key Words Simple Screw Machines Lever Inclined Plane Fulcrum Wedge
    4. 4. What is a Simple Machine?A simple machine has few or no moving parts. Simple machines make work easier
    5. 5. 3 types of simple machines The inclined plane The Wedge The Screw
    6. 6. What is an inclined plane?A sloped surface An inclined plane allows you to exert your input force over a longer distance Ideal Mechanical Advantage =
    7. 7. Inclined Planes An inclined plane is a flat surface that is higher on one end Inclined planes make the work of moving things easier
    8. 8. Increase Force Increase distance When the output  When the output force is greater force is less than than the input force the input force the the mechanical mechanical advantage is advantage is less greater than 1. than 1. • If only the direction changes, both the input force and output force will be the same
    9. 9. What is efficiency? Output Work / Input work x 100%
    10. 10. EFFICIENCY Theefficiency of a machine compares output work to input work Output Work 100 Input Work
    11. 11. Inclined Planes How do Inclined Planes work?
    12. 12. WedgesCan your teeth be machines?
    13. 13. Wedges Two inclined planes joined back to back. Wedges are used to split things.
    14. 14. Ideal Mechanical AdvantageInclined Plane Wedge Divide the length  Length of the plane of the incline by divided by its width the height  Longer and thinner the wedge is, greater the mechanical advantage
    15. 15. ScrewsA screw is an inclined plane wrapped around a shaft or cylinder. The inclined plane allows the screw to move itself when rotated.
    16. 16. Mechanical Advantage ofScrew length of thread around the screw by the height of the screw
    17. 17. LEVERS
    18. 18. Objectives How are levers classified
    19. 19. What is a Lever?A lever is a rigid bar that is free to pivot, or rotate on a fixed pointThe fixed point that the lever pivots around is called the fulcrum
    20. 20. Levers-First Class In a first class lever the fulcrum is in the middle and the load and effort is on either side Think of a see-saw
    21. 21. Levers-Second Class In a second class lever the fulcrum is at the end, with the load in the middle Think of a wheelbarrow
    22. 22. Levers-Third Class In a third class lever the fulcrum is again at the end, but the effort is in the middle Think of a pair of tweezers
    23. 23. Ideal Mechanical Advantage IdealMechanical Advantage = Distance from fulcrum to the input force Distance from fulcrum to the output force
    24. 24. Putting Machines Together
    25. 25. Key Words Pulley Wheeland Axle Compound Machine
    26. 26. Ideal Mechanical Advantage Ideal Mechanical Advantage = Radius of Wheel Radius of Axle
    27. 27. Compound Machines Howdo Compound Machines work?  Withina compound Machine, the output force of one simple machine becomes the input force another simple machine
    28. 28. Wheels and Axles The wheel and axle are a simple machine The axle is a rod that goes through the wheel which allows the wheel to turn Gears are a form of wheels and axles
    29. 29. PulleysA Pulley is a simple machine made of a grooved wheel with a rope or cable wrapped around it. (A pulley needs a rope, chain or belt around the groove to make it do work)
    30. 30. Simple Machines Simple Machines can be put together in different ways to make complex machinery
    31. 31. Give examples for each classof lever Hwpage: 99-101

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