======Equal and Opposite Forces======

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[[days:fall2009daybyday:fall2009day13:start|Fall 2009-Day 13]]\\
[[activities:motion:start|Force and Motion Activities]]\\

The students all stood in a line across the room to model the concept of force. The four students on the left, pulled to the left. The four students on the right, pulled to the right. They found that each individual student was pulling with the same amount of gumption, but the two sides of the line were pulling in opposite directions.
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Using a force measurement tool, the two students in the middle discovered that they were not only pulling in the opposite direction, but they were also pulling with the same amount of force in the opposite direction.
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This opening activity about force stimulated conversations about force. With partners, the students shared everything they knew about force. Then, as a class, the students' knowledge of force was discussed. Topics related to force that came up included gravity, pounds, F=mxa, mass, acceleration, etc.