Center of Gravity of a Weighted Rod
Brief Description
The weighted pvc pipe is used to demonstrate how to find the center of mass of an irregular rod. If you hold up the pipe with one finger at each end and slowly bring your fingers together, they will meet each other at the center of mass. This is because the amount of force on one finger depends on the placement of the center of mass relative to it. That is, if one finger is closer to the center of mass than the other, then the contact force between it and the pipe is stronger than with the other finger. This leads to more friction on the finger that’s closer to the center of mass, and will thus move less than the other finger as you bring them together.
Materials
Weighted pvc pipe
Performing the Demo
To perform this demo, simply balance the rod on two fingers and bring them together towards the middle slowly. Where they meet will be the center of mass.
Other Notes
This demonstration can be done with any irregular rod (see 1J10.09).