demonstrations:floating_paper_clip
Floating Paper Clip
Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required
Categories: Fluids and Surface Tension
Alternative titles:
Summary
A paperclip, normally too dense to float, can rest on the surface of water by using tissue paper and surface tension.
Procedure
- Fill a bowl with clean water.
- Attempt to place a paperclip on the surface, notice that it sinks.
- Tear a small piece of tissue paper and place it on the water’s surface.
- Carefully set a dry paperclip flat on top of the tissue, avoiding direct contact with the water.
- Push down the tissue until it sinks.
- Adding a drop of detergent will cause the paperclip to sink because the surface tension has been broken.
Links
Floating Paper Clip (Surface tension) Experiment - Kids Fun Science:
📄🎞️ Make a paperclip float - Science Bob: https://sciencebob.com/make-a-paperclip-float/
Variations
* Test how many paperclips the water surface can hold before it breaks.
- Try bending the paperclip into different shapes to see if it changes floating ability.
- Compare water to other liquids (such as milk, juice, or soda) to test which has stronger surface tension.
Safety Precautions
None
Questions to Consider
- Why does the paperclip sink when placed directly into the water?
- How does surface tension allow the paperclip to stay on top of the water?
- Why does the tissue paper sink while the paperclip remains floating?
- Which liquids seem to have the strongest surface tension?
- How do insects like water striders use surface tension in their environment?