PURPOSE: Demonstrate how the three classes of levers operate and how they are different.
DESCRIPTION: Referring to the three photographs above:
First class lever (right): the pivot is between the load and the applied force (push down with hand or pull down with spring scale at right of photo).
Second class lever (left): the load is between the pivot and the applied force.
Third class lever (center): the applied force is between the load and the pivot.
SUGGESTIONS: Look this over before class; you must change around the various components during the lecture.
REFERENCES: (PIRA 1M20.40)
EQUIPMENT: Two-meter demonstration scale, 20 Newton self-weighing spring scale, 20 Newton normal spring scale, mass hanger with three 1 kg masses, string loop.
SETUP TIME: 10 min.
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