Tuesday, February 9, 2010

Cool Science Fair Idea

For anyone with a project coming up or if you just have a lot of time on your hands...


A fun project is the Schrodinger's Cat Box. You need a mild source of
radioactivity (I use scrapings from old "luminous" watches I get at flea
markets). I make a box out of plywood except that two sides are small
celled Nomex honeycomb (<.125") cut to three inch thickness. One honeycomb
side is covered with onion skin paper and the other is left open. A strong
light is positioned outside the open celled honeycomb wall and is directed
into the box. The radioactive scrapings are smeared across the light lens
with a bit of glue. Inside the box I put the sensor to a Geiger counter
(borrow one from your local high school). The counter is connected to a
fast relay which, when closed by an alpha particle from the scrapings,
lights the light. Now, a small, live animal (cat) is placed into the box.
One stands behind the onion skin paper side of the box and plugs in the
Geiger Counter. With no light the alpha particles are few and are not
sufficient to turn on the light. The light is switched the first time with
a switch which is in parallel with the relay. Instantly you can see the
shadow of the animal on the onion skin paper. Then, as the cat moves, the
light and rush of alpha particles turn the light on and off, strobe like,
and you can see that sometimes the animal is not there, or some part of him
is gone! It's quantum uncertainty can be measured. It proves that there
are two states for the animal (and everything else) -- existence and
non-existence. No harm comes to the animal, by the way.

1 comment:

  1. That's seriously way cool...not the physics of it, because I don't have any idea what you are talking about. But I think it's awesome that my aunt actually has a kid's science project up her sleeve that entails a "mild source" of radio activity.