How to Graph a Radioactive Decay Simulation

You can model radioactive decay using a simple exponential.

Radioactivity refers to the process in which an atomic nucleus emits a particle in order to lose energy. There are three types of radioactive decay and these are known as alpha, beta and gamma radiation. The time taken for a decaying atom to fall to one half of its initial amount is known as a half life, and this is a useful measurement in determining how long a radioactive species is likely to be dangerous. You can simulate radioactive decay with a simple exponential function.

Things You'll Need

• Graph paper
• Calculator

Instructions

1. Draw a table and label the headings "Time (s)" and "Number atoms." Fill the table in with the radioactivity simulation. You can simulate radioactivity using a simple exponential of the form N(t) = N x Exp (-0.693t/Thalf). Where N is the initial number of radioactive atoms, t is the time, and Thalf is the half life. Plug in a range of values for t into the equation to get number of radioactive atoms.

2. Draw the axes of the graph. The two axes are lines that run perpendicular to one another and meet at the origin. The horizontal line is known as the X-axis and the vertical line is known as the Y-axis.

3. Label the axes. Label the X-axis "Time (s)" and the Y-axis "Number of atoms".

4. Plot the values from the table onto the graph. Plot the time along the X-axis and the number of atoms on the Y-axis. The finished graph should look like a classical exponential decay where the number of radioactive atoms reduces with time, rapidly at first, and then more slowly.

References

• Georgia State University: Radioactive Half-Life