
Nuclear Chain Reactions with Dominoes
Easy
How does a nuclear reactor control a chain reaction? You can model the process with dominoes and a ruler.
Arrange dominoes in a branching pattern. One domino in the first row knocks over two in the second row. Those two knock over four. The reaction doubles with each row.
Now set up a straight line of dominoes and place a ruler between two of them. Knock over the first one. The ruler stops the chain just like a control rod stops neutrons inside a nuclear reactor.
Hypothesis
The hypothesis is that a ruler can be used to control a domino chain reaction, just like a control rod in a nuclear reactor.
Science Concepts Learned
Nuclear Chain Reaction
Splitting one atom releases energy that splits more atoms. Each time it happens, the reaction doubles. Dominoes arranged in a branching pattern model this process: one knocks over two, and those two knock over four. When you place a ruler between two dominoes, the chain stops cold — just as a control rod stops neutrons inside a nuclear reactor.
Method & Materials
You will arrange dominos in a pattern and knock over the first domino. Then, you will use a ruler to control the chain reaction.
You will need a bunch of dominos, a ruler, and a flat table that doesn't shake.
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See what’s includedResults
The experiment showed that a ruler can be used to control a domino chain reaction, just like a control rod in a nuclear reactor. The observation that stands out is that not all the dominos fell over when the ruler was used.
Why do this project?
This science project is interesting and unique because it demonstrates a nuclear reaction using simple materials.
Also Consider
Experiment variations to consider include using different materials to control the chain reaction, such as a book or a block of wood, or using different patterns of dominos.
Full project details
Additional information and source material for this project are available below.Related videos
These videos explain the science behind this project and demonstrate key concepts used in the experiment.
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