PURPOSE: To demonstrate the concept of density through use of bricks of similar size but very different weights.
DESCRIPTION: This demonstration consists of four bricks of the standard "brick" size and shape, made respectively from: foam, concrete, steel, and lead. Because the sizes are similar and the weights different, the feature creating the difference must be the density, or mass per unit volume.
SUGGESTIONS: Let the students handle the bricks.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Foam, concrete, steel and lead bricks.
SETUP TIME: None.