The Spinning Can

A can with small angled holes near its base will spin when filled with water and suspended.

1. Take an empty soda can with its pull-tab intact (or a soup can).
2. Use a nail or ice pick to make four small, equally spaced holes around the bottom rim.
3. As you punch each hole, push the tool sideways so each hole is slanted in the same direction.
4. Bend the can’s pull-tab upward and tie fishing line to it. For a soup can, punch two holes near the top rim and run string through them.
5. Submerge the can in water until it is completely full.
6. Lift the can using the string over a bucket or tub.
7. Watch as water streams out of the slanted holes, causing the can to spin.

Spinning Soda Can Experiment (Newton's Laws of Motion) - Kids Fun Science:

📄 The Spinning Can - cmste.uregina.ca: https://www.cmste.uregina.ca/Quickstarts/spinningcan.html

• Try different numbers of holes (2, 3, 4, or more) to see how it affects spinning speed.
• Vary hole sizes to compare how water flow rate changes the can’s motion.
• Test different can sizes (small soda can vs. large soup can).
• Add a fishing swivel to the string above the can for smoother rotation.

• Use caution when punching holes to avoid slipping and cutting yourself.
• Keep the workspace dry to prevent slipping hazards from spilled water.
• Supervise younger students when handling sharp tools.

• Which of Newton’s laws explains why the can starts to spin? (Newton’s Third Law: the water pushes one way, the can reacts by spinning the opposite way.)
• How does the number of holes affect the spinning speed? (More holes increase force, but also drain water faster, affecting rotation time.)
• Why must the holes be slanted instead of straight? (The angled jets produce sideways thrust to create torque; straight jets would just flow downward.)
• How does this experiment relate to real-world applications? (It demonstrates principles similar to jet propulsion, rockets, and turbines.)