1 / 14

Levers

Levers. Jason Day. What is a lever?. A lever is an object consisting of a rigid bar or plank that pivots at a certain point. Often used to lift an object at a second point when applying force to a third point. Picture. Parts.

ekram
Télécharger la présentation

Levers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Levers Jason Day

  2. What is a lever? • A lever is an object consisting of a rigid bar or plank that pivots at a certain point. Often used to lift an object at a second point when applying force to a third point.

  3. Picture

  4. Parts • The first point (where the bar or plank pivots) that is called the “fulcrum.” • The second point (the fraction of the bar or plank holding up the object that is to be lifted) is called the “resistance arm.” • The third point (the fraction of the bar or plank that force is applied to) is called the “effort arm.”

  5. Picture Effort Arm Resistance Arm Object Applied Force Fulcrum Pivot Bar or Plank

  6. How to Calculate Mechanical Advantage MA= Effort Arm/Resistance Arm

  7. Pictures and Stuff MA = 3 2 - 3 5 1 MA = 2.6 MA = 1 MA = .4 8 4 4 3

  8. What is Mechanical Advantage? • Mechanical advantage is the ratio of output force to the input force. • It is used to calculate the efficiency of a machine. • The higher the number the more efficient the machine is. The lower the number the less efficient the machine is.

  9. Types of Levers • There are three different types of levers. • A first class-when the fulcrum is in between the where the force is applied and the object or load. • A second class-when the object or load is in between the pivot and where the force is applied. • A third class-when the point at which the force is applied is between the object or load and the pivot.

  10. Pictures

  11. Examples of a First Class Lever • A see saw • A pair of scissors • Pliers

  12. Examples of a Second Class Lever • A stapler • A wheel barrow • A nail clipper

  13. Examples of a Third Class Lever • Tweezers • Fishing Rod • Tongs

  14. Recap • Levers are used to move object. Usually. • Levers can be found in many different places. • To calculate Mechanical Advantage of a lever you divide the length effort arm from the length resistance arm. (see page 6) • There are different of levers. First Class, Second Class, and Third Class. (see pages 10-13)

More Related