PURPOSE: To illustrate a volume perception paradox.
DESCRIPTION: Water filling the graduated cylinder is poured into the apparently smaller spherical flask.
SUGGESTIONS: Before pouring the water, ask your students if the amount of water in the cylinder will (a) not fill up the sphere, (b) fill up the flask to somewhere along the cylindrical neck, or (c) fill up the flask before the cylinder is emptied. Click your mouse on the photograph above for the answer.
See Question of the Week #14 for information on using this demonstration to enhance class involvement.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Graduated cylinder, flask, and water.
SETUP TIME: 10 min.