How does a slow-rolling steel ball launch another ball fast enough to blur in a photo? A magnetic chain reaction does the work. Each magnet in the line adds energy to the next ball.
You tape four strong magnets along a grooved ruler. Two steel balls sit to the right of each magnet. Roll one ball slowly toward the first magnet. It snaps in and transfers energy through the group. The last ball shoots toward the next magnet even faster.
The chain reaction builds speed at every stage. The final ball fires off the end of the ruler and hits a target hard.
Hypothesis
The hypothesis is that a magnetic chain reaction can be used to launch a steel marble at a target with high speed.
A slow-rolling steel ball can launch another ball fast enough to blur in a photo. The trick is a magnetic chain reaction, where each step adds energy to the next. Tape four strong magnets along a grooved ruler and place two steel balls to the right of each magnet. Roll one ball slowly toward the first magnet. It snaps in, transferring energy through the group — and the last ball shoots toward the next magnet even faster. Each magnet in the line adds energy to the next ball, so speed builds at every stage. The final ball fires off the end of the ruler and hits a target hard.
Kinetic energy is the energy something has because it is moving. You tape four magnets along a grooved ruler and set a steel ball in the groove. The final ball fires off the end of the ruler and hits a target hard, showing it carries a large amount of kinetic energy.
Method & Materials
You will tape four magnets to a wooden ruler, place nine steel balls to the right of each magnet, and set a steel ball in the groove to the left of the leftmost magnet.
You will need a wooden ruler, Scotch brand transparent tape, four magnets, nine steel balls, and a sharp knife.
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This project demonstrates the power of magnetism and kinetic energy. When the first ball is released, it is attracted to the first magnet and transfers its kinetic energy to the other balls, causing them to speed up and hit the target with considerable force.
Why do this project?
This science project is unique because it uses a simple chain reaction to launch a steel marble at a target with incredible speed.
Also Consider
Experiment variations to consider include changing the distance between the magnets and using different types of magnets.
Full project details
Additional information and source material for this project are available below.
