1 / 11

Elevators

Elevators. Jackscrew Elevator. Screw provides mechanical advantage Ramps (screw’s threads) provide mechanical advantage Translate ramp a long distance with a small force Ramp moves up a small distance with a large force. Jackscrew Elevator Problems. Sliding friction heat wear

terrysanchez
Download Presentation

Elevators

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. Elevators

  2. Jackscrew Elevator • Screw provides mechanical advantage • Ramps (screw’s threads) provide mechanical advantage • Translate ramp a long distance with a small force • Ramp moves up a small distance with a large force

  3. Jackscrew ElevatorProblems • Sliding friction • heat • wear • Need a long screw

  4. Hydraulic Elevator • Pressure provides mechanical advantage force = pressure x surface area small force / small area = large force / large area

  5. Hydraulic ElevatorProblems • Doesn’t store energy between trips • going up, pump provides energy • going down, gravitation potential energy is converted to heat • Needs a long piston

  6. Cable Lift Elevator • Pull from above with a long cable

  7. Tug-of-War Each team pulls on a rope with a force of 500 pounds in opposite directions. What is the tension in the rope? • 500 pounds • 1000 pounds

  8. Tension • Each portion of rope pulls on neighboring portions with a certain force tension = force exerted on each end of rope

  9. Pulleys • Redirect forces • amount of force provided by tension • direction of force along rope

  10. Multiple Pulleys • Mechanical advantage • same tension in every rope segment • each segment pulls up with a force equal to this tension • Small force over a long distance provides large force over a small distance

  11. Counterweights • Balanced seesaw • Total mass rising or falling is small • Requires less power to move

More Related