1Q20.15 - Angular Momentum - Rotating Air Table

See procedure.
Code Number:
Demo Title:
Angular Momentum - Rotating Air Table
Angular Momentum
Area of Study:
Rotating Air Table, Masses, Pulley, String, Meter Stick, Stop Watch.

Wrap several turns of the string around the circumference of the air table.  Place the pulley at the height where the string will run horizontally off the air table.  Time how long it takes for the mass to reach the ground from a measured height, and the number of rotations of the table for that distance.  

Some measurements are as follows:

Mass of rotating table top = 11.3 Kg.  

Radius = 25.5 cm 

Hanging Mass = 100gr.

Height from floor = 90cm. 

Time of fall = 3.45 s  

Calculated alpha = .61 radians / s2  

Theoretical alpha = .67 radians / s2

  • John Sherfinski, "A Rotational Dynamics Problem with Friction and Calculus", TPT, Vol. 39, # 3, Mar. 2001, p. 150.

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