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Further Investigations

• Create a first class lever that acts as a distance magnifier. That is, make the distance the potatoes are raised be twice as great as the distance you pull the force sensor. Use two rulers, one to measure how far the potatoes move, and the other to measure how far you must pull the force sensor.

  Make sure to think about:

  What is the distance of the potatoes from the fulcrum, compared to the distance of the force sensor from the fulcrum?

  How does the force sensor reading compare to the weight of the potatoes?

  Draw a diagram showing the load, the fulcrum, and the applied force.

  The ratio of distance traveled by the applied force, divided by the distanced traveled by the load, is the Mechanical Advantage (MA) for a lever. Determine the MA of your device.

  
  

• Create a first class lever that acts as a distance reducer. That is, make the distance the potatoes are raised be half as great as the distance you pull the force sensor. Use two rulers, one to measure how far the potatoes move, and the other to measure how far you must pull the force sensor.

  Make sure to think about:

  What is the distance of the potatoes from the fulcrum, compared to the distance of the force sensor from the fulcrum?

  How does the force sensor reading compare to the weight of the potatoes?

  Draw a diagram showing the load, the fulcrum, and the applied force.

  The ratio of distance traveled by the applied force, divided by the distanced traveled by the load, is the Mechanical Advantage (MA) for a lever. Determine the MA of your device.

  
  

• A pulley system usually acts as a force magnifier. That is, the applied force can be smaller than the load that it lifts. But there's a trade-off: the force sensor must be pulled a longer distance than the load. If the force is less, the distance is greater.

  Make sure to think about:

  How does the applied force compare to the weight of the potatoes? Test this idea. Build a pulley system such that the force sensor moves 20 cm in order to raise the potatoes 10 cm.

  The ratio of distance traveled by the applied force, divided by the distanced traveled by the load, is the Mechanical Advantage (MA) for a lever. Determine the MA of your device.

  
  

• If you have 3-5 pulleys, build a system such that the force sensor moves 40 cm in order to raise the potatoes 10 cm.

  Make sure to think about:

  How does the applied force compare to the weight of the potatoes?

  Determine the Mechanical Advantage of your pulley system.

  
  

• An inclined plane usually acts as a force magnifier. That is, the applied force is less to pull a load uphill along a slope than if the load were lifted straight up. But there's a trade-off: the load must travel a longer distance to get to the same height. If the force is less, the distance is greater. For example, the Egyptians used long gradual ramps to drag very heavy stones to the tops of the pyramids.

  Make sure to think about:

  How does the applied force compare to lifting the potatoes straight up? Test this idea. Build an inclined plane where the length of the ramp is four times greater than its height.

  The ratio of vertical height traveled, divided by the length of a ramp, is the Mechanical Advantage for a ramp. Determine the Mechanical Advantage of your system.