Levers - Three Classes

Purpose

Demonstrate how the three classes of levers operate and how they are different.

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.

Suggestions

Look this over before class; you must change around the various components during the lecture.

Setup Time

10 min.

Images

b3-02

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.