14 2 Work And Machines

|
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
 72 views
of 11

Please download to get full document.

View again

Description
1. 14.2 Work and Machines How Do Machines Make Work Easier? How Are Work Input and Work Output Related for a Machine? 2. Machines Do Work <ul><li>Machines =…
Share
Transcript
  • 1. 14.2 Work and Machines How Do Machines Make Work Easier? How Are Work Input and Work Output Related for a Machine?
  • 2. Machines Do Work <ul><li>Machines = are devices that change force </li></ul><ul><li>Ex. Car Jack, Lug wrench,Car </li></ul><ul><li>Machines make work easier </li></ul>
  • 3. Machines Do Work <ul><li>Machines change the size of force needed </li></ul><ul><li>Machines change the direction of a force </li></ul><ul><li>Machines change the distance over which a force acts </li></ul>
  • 4. Work Input and Work Output <ul><li>Input Force- is the force you exert on a machine. </li></ul><ul><li>Input Distance- the distance the input force acts through. </li></ul><ul><li>Work Input- work done by the input force acting through the input distance. </li></ul>
  • 5. Work Input and Work Output <ul><li>Equation: </li></ul><ul><li>Work input = the input force X input distance . </li></ul><ul><li>Equation: </li></ul><ul><li>Work Output = the output force X output distance. </li></ul>
  • 6. Work Input & Work Output <ul><li>Output Force- the force exerted by a machine. </li></ul><ul><li>Output distance- the distance the force is exerted through. </li></ul>
  • 7. 14.3 Mechanical Advantage and Efficiency How Does the Actual Mechanical Advantage of a Machine Compare to Its Ideal Mechanical Advantage? Why Is the Efficiency of a Machine Always Less Than 100%?
  • 8. Mechanical Advantage <ul><li>Mechanical Advantage of a machine is the number of times a machine increases an input force </li></ul>
  • 9. Actual Mechanical Advantage <ul><li>Mechanical Advantage that is measured </li></ul><ul><li>Actual Mechanical Advantage = </li></ul><ul><li>Output Force / Input Force </li></ul>
  • 10. Ideal Mechanical Advantage <ul><li>Mechanical advantage in the absence of Friction </li></ul><ul><li>Calculation depends on location of forces and distances over which they act </li></ul><ul><li>Ideal Mechanical Advantage = </li></ul><ul><li>Input distance / Output distance </li></ul>
  • 11. Efficiency <ul><li>Is the percentage of work input that becomes work output. </li></ul><ul><li>Efficiency = </li></ul><ul><li>Work output / Work input X 100%. </li></ul><ul><li>Friction makes the efficiency less than 100%. </li></ul>
  • Related Search
    We Need Your Support
    Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

    Thanks to everyone for your continued support.

    No, Thanks