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How to Move a Load With a Small Force & Levers

"Give me a Place to Stand and I Will Move the Earth." Thus spake Archimedes about his lever --- an arrangement as simple as a board and a rock. But the lever has the ability to multiply force. The amount of energy put into moving one end of a lever is the same as the energy that can be extracted from the other end. The energy change is the product of force times distance, so by manipulating the distances, the force can be controlled.

Things You'll Need

Lever
Fulcrum
Heavy object

Instructions

- 1
  
  A load like this looks imposing, but the right lever --- properly placed --- can tip it right over.
  
  Determine the ratio of the force needed to move the load.
  
  For example, if you weigh 150 pounds, that's the maximum force you can apply. If you want to move a 675 pound load then the maximum force ratio is 675/150, or 4.5. If you don't want to use all your weight, double that to 9 to provide some margin.
- 2
  Measure the length of the board.
  
  For now, assume you have a 10-foot-long board.
- 3
  Determine the fulcrum location needed to create the force ratio determined in Step 1. The ratio of the distances will be the same as the ratio of the forces.
  
  For the example, the force ratio is 9 so the distance ratio will be 9 as well. That is, the fulcrum will be 1 foot from one end and 9 feet from the other, making a ratio of 9/1, or 9.
- 4
  Wedge the lever under the load, place the fulcrum --- a block, a rock, anything solid and stable --- at the location determined in the previous step.
- 5
  Push down, and watch your 75 pounds of effort get multiplied enough to lift that 675-pound load.

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