1 / 15

Mechanical Advantage

Mechanical Advantage. MA tells how much easier it is to use a simple machine than to not use it. Huh? (translation, please!). Mechanical Advantage (MA). You have a choice between two simple machines. One is easier to use than another. You will choose the one that is easier to use, right?

wei
Download Presentation

Mechanical Advantage

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. Mechanical Advantage • MA tells how much easier it is to use a simple machine than to not use it. • Huh? (translation, please!)

  2. Mechanical Advantage (MA) • You have a choice between two simple machines. One is easier to use than another. You will choose the one that is easier to use, right? • MA is a property of simple machines that quantifies what we mean by “easier”.

  3. Simple Machine Work Work Simple Machine Force D F Distance Conservation of Energy Remember: Work = Force x Distance

  4. Conclusions • Work into a machine equals work out of a machine. • Simple machines do not make work go away. They make work easier to do by making the input force less, for example. • You don’t get something for nothing. You must “pay” for the reduced input force by moving greater distances.

  5. Example: Inclined plane • You need to move a box from the floor to a table, 1 meter off the floor. • You can raise the box with just your muscles (no simple machine). You push with 50 N of force. • W = F x d; W = 50 N x 1 m = 50 Nm • If you use a 5 meter inclined plane, you push with only 10 N to move the box up the ramp. • W = F x d; W = 10 N x 5 m = 50 Nm

  6. F Distance Simple Machine Force D F = input force (Fi) Force = (Fo) Distance = input distance (di) D = (do) Quantifying Mechanical Advantage Input side Output side So, using the forces only, MA is the ratio of output force over input force.

  7. Quantifying MA • MA = Fo / Fi • To easily remember this, think of a phrase using 2 words that begins with fo______ and fi_________. • How about food fight?

  8. Problem A force of 200 N is applied to a machine in order to lift a 1,000-newton load. What is the mechanical advantage of the machine?

  9. Answer MA = Fo / Fi MA = 1000 N / 200 N MA = 5 Notice that the answer doesn’t have any units. Why?

  10. Problem 1 1. A machine is designed to push an object with a weight of 12 N. If the input force for the machine is set at 4 N, what is the mechanical advantage of the machine?

  11. Answer 1 1. MA = 3

  12. Problem 2 2. A machine is required to produce an output force of 600 N. If the machine has a mechanical advantage of 6, what input force must be applied to the machine?

  13. Answer 2 2. Fi = 100 N

  14. Problem 3 3. An input force of 35 N is applied to a machine with a mechanical advantage of 0.75. What is the size of the load this machine could lift (how large is the output force)?

  15. Answer 3 3. Fo = 26.25 N

More Related