Block and Cylinder
- Purpose: Demonstrate principles of stability.
- Balance styrofoam block (with pencils removed) on pvc cylinder
(non-velcro side to non-velcro side). Block is stable if balanced wide-base-down,
and unstable if balanced thin-base-down. To demonstrate the relationship between
the stability of the block and the location of its center of mass: insert
a pencil into the block, as shown above; place the block onto the cylinder
(velcro to velcro) such that the pencil makes contact with the attached paper;
carefully rock the block back and forth to get a smooth pencil trace on the
sheet of paper. The pencil trace represents the height of the block's center
of gravity as a function of angle. (The velcro simply keeps the block from
slipping while making your trace). In theory, the block should balance if
the height of the block is smaller than the diameter of the cylinder, and
shouldn't balance if the height of the block is larger than the diameter
of the cylinder (assuming density of block is uniform).
- Located in L02, section B4