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

Extra Credit: Measure the moment of inertia of a human body

Predict and measure the moment of inertia of a human body.

This project may be done by teams of 1-3 individuals. The goal is to measure the moment of inertia of a human body (live or dead). Pick a body, and some particular arrangement of its limbs and torso (spread-eagle, fetal position, etc.). First, based on the mass and size of the body and its limbs, predict the moment of inertia. Write explicitly any assumptions you make about your calculations. Draw a picture of the body in your chosen position, and use it to illustrate your calculations.

Next, design an experiment from which the moment of inertia can be calculated. For example, you might hang someone from a hook by the seat of his pants, tip him to a horizontal position, then release him and measure the time it takes him to revert to the vertical. Draw a picture of the experiment, showing all relevant details. Carry out the experiment, making at least three trials. Record the results of each trial. Calculate the average moment of inertia.

Compare the measured moment of inertia to the predicted one. How close was your prediction? Can you explain any differences?

Submit a report which contains the pictures and descriptions of your experiment, as well as the results. You may also include interesting items you discovered during the course of the procedure.


This page maintained by Michael Richmond. Last modified Mar 8, 1997.

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