Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.

The Force Plate

We will use a force plate (essentially a digital bathroom scale that connects to the Labpro) to look at your power of prediction. When you stand still on the plate, it will read a value equal to your weight, (mass)*(g). Suppose now that you make a three-part motion:

  1. start with bent knees, standing still on the plate,
  2. straighten the knees, and ...
  3. jump off the force plate.

(a) Draw a free body diagram of YOU for each part of the motion. Remember it should show you free of your surroundings, with forces drawn indicating the location at which each force is applied. Write information about acceleration off to the side somewhere (if you know it), and draw a little set of coordinate axes.

(b) Use the information learned from the free body diagram to predict the shape of a force-time graph.

And now, we'll actually do the experiment. Sketch the actual force-time graph below.

Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.