Simulations

Half Life of Dice

The Half-life of Dice is a useful illustration of the random nature of radioactivity and produces a good graph to plot.

Instructions:

Take ten bags with 100 x 1cm3 cubes in each.

One side of each cube needs to be painted in some colour(best done before you cut them up if you are making them in the technology lab!)

Give the bags of 'dice' are to small groups of pupils.

They must throw the dice into a small tray and remove any that fall 'coloured face upward'.

Then they must count and record the number remaining and throw them again.

This is repeated until all are removed.

The results can be assimilated using a simple spreadsheet package.

In this way a random decay with a probability of 1 in 6 can be plotted with 1000 events investigated. Links with the mathematics department to work on probability are a possibility here.

Popping Popcorn simulation of random decay

Again showing the random nature of decay the following simulation popping popcorn works well.

(Care with safety! … Do a full risk assessment!).

Instructions:

Pre-heat a popcorn popper.

Mark a few of the kernels with a felt-tipped pen.

Place about 20 popcorn kernels in the air popper. (Using only a few kernels will prevent the kernels from being obscured by the popped corn).

Pop the popcorn.

Record the time it takes for a coloured kernel to pop.

Repeat with fresh kernels.

There is no way to predict the exact time at which a coloured kernel will pop, but it is possible to determine the time it will take most of them to!

Transmutation can be simulated by playing a game.

You need a supply of two sets of coloured balls or beads.

The beads are placed in a bowl to represent the protons and neutrons in the nucleus of an atom.

Beads/balls representing the particle emitted are taken out and the remaining nucleus' characteristic can then be worked out by counting the number of protons and neutrons left in the bowl. Its name can be looked up on a periodic table.

An 'exchange pot' needs to be available so that beta and positron emission can be modelled.

A card explaining the rules must be put with the 'pot'.

What ever represents a proton can be exchanged for a neutron and a positron and whatever represents a neutron can be replaced by a beta particle and a proton.