This
exhibit models radioactive decay of nuclei and fundamental particles
with wooden cubes. There are 100+ hardwood cubes each with one
side painted red. These cubes are placed into a wicker bowl and
tossed onto a table. The cubes that land red side up are removed
and placed into one column at the bottom left edge of the table.
The smaller number of remaining cubes are then placed into the
basket and tossed again. The cubes that land with their red side
up are removed again. The process continues until there are no
cubes left.
The exhibit teaches about halflife; half of all the remaining
cubes "decay" after every 3 tosses. The decreasing columns
of cubes show an exponential decay in height. This exponential
decay results from the constant 1 in 6 probability that each cube
will decay on each throw.
The random fluctuations in the height of each pile are also visible
in the nonsmooth profile of a curve connecting the heights of
the columns of cubes.
The crash of the cubes from the basket is such an interesting
sound that young children spend time throwing the cubes from the
basket and arranging them in piles.
The "decayed" blocks form an exponential pattern of
piles.
