Half-Life Dice Simulation

Decay curve

Experiment Instructions

Aim: To model radioactive decay and estimate a half-life by rolling and removing dice.

  1. Choose a starting number of dice, then click Roll the dice.
  2. Every die that lands on its dark face has "decayed" — click each one to remove it from the tray.
  3. Count how many dice are left, type the number in, and click Record result.
  4. Repeat: roll, remove the decayed dice, count, record — until very few dice remain.
  5. Use the graph to estimate how many rolls it takes for the number of dice to halve — this is the half-life of the simulation, in rolls.

Results

Roll Dice remaining Dice decayed this roll

Student prompts

  • Why is the dark face a good model for radioactive decay, even though real nuclei don't roll dice?
  • Roughly how many rolls does it take for the number of dice to fall from 100 to 50? From 50 to 25?
  • Is the number of rolls needed to halve the count always exactly the same? Why not?
  • How would using 20 dice instead of 200 change how smooth your decay curve looks?
  • What single change to the dice would make the "half-life" shorter?