Skip Ribbon Commands
Skip to main content

1Q40.10 - Rotating Chair with Weights

The Web Part cannot find an InfoPath form in the specified location. Either the location does not have an InfoPath form associated with it or it is on a different site collection. Modify the Web Part Properties and select a list or library on the current site.

​1Q40.10 - Rotating Chair with Weights

Title1Q40.10 - Rotating Chair with Weights

Demonstrate the conservation of angular momentum.

Assembly Instructions

The "Rotating Chair with Weights" sits on a wheeled movable base and is covered in a plastic dust cover. Remove the cover and wheel the appartus into its position in the classroom in front of the lecture bench. Remove the weights and set aside. Tip the chair over onto its back to be able to remove the wheeled base. There are three plastic cups that mount on the metal screws at the base of the chair (these are necessary for lecture hall use). Place one cup on each screw and carefully bring the chair back to its upright position. You may have to adjust the screws so that the chair is level and doesn't turn on its own. Once it is level, one may sit on the chair and buckle themselves up for a fun, safe ride.

Setup Time10
Operation Time5
Preview Time5
Operation Instructions

For this demonstration, use the seat belt.  The demonstrator, holding a 5- or 10-lb weight at arm’s length in each hand, starts into slow rotation on the chair or the platform. Drawing the weights toward the body increases the rotation rate. If the arms are extended again, the rotation will slow down. The demonstrator can usually feel a Coriolis force, i.e. one is required not only to exert a radial force to pull the weight in, but a force perpendicular to this one in order to make the weight follow the radial path.

Demo on DimeNo
PIRA 200Yes
Export Instructions (if different)
Our export version consists of a wooden turntable.  Stand on the turntable and proceed like on the rotating chair.
Category1 Mechanics
Subcategory1Q - Rotational Dynamics
Keywordsfigure skater
Construction Information
rotating chair
weight - 5 lbs
floor protector disk
transport cart for rotating chair