TOPIC:

ID Code: C4-51
Purpose: Demonstrate weightlessness in free fall.
Description: A small mass is attached to the inside center of a beaker using a light spring. The cup is held upside down, with the mass hanging out of the cup, then released from rest. Ask the students what will happen when the cup is released: (a) the mass will extend the spring, like a parachute, due to air pressure pulling on the cup, (b) the mass will be pulled up into the cup by the spring, or (c) the cup will fall with the mass in its original position. Click on the photograph above to view the action.
Availability: Available

See the Physics Question of the Week for 5/12/2014 for an example of how this demonstration can be used in class interaction and discussion: lecdem.physics.umd.edu/question-of-the-week-archive.html