demonstrations:inseparable_books
Inseparable Books
Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required
Categories: Force
Alternative titles: Friction Between Notebook Pages
Summary
Two notebooks are interleaved page by page and become nearly impossible to pull apart.
Procedure
- Place two notebooks on a flat surface with their bindings facing inward.
- Overlap the covers so they are completely aligned.
- Starting near the spine, alternate one page from each notebook, interleaving them page by page until the books are fully intertwined.
- Hold the notebooks just inside the bindings and attempt to pull them apart.
- Try with a partner pulling one notebook while you pull the other. Notice how the pages hold tightly together.
Links
Inseparable Books Experiment - Kids Fun Science:
📄🎞️ Inseparable Books - Steve Spangler: https://stevespangler.com/experiments/inseparable-books/
Variations
- Try using different types of paper (glossy, thin, thick) to compare how friction changes.
- Increase or decrease the number of interleaved pages to test the effect on pulling difficulty.
- Use smaller or larger notebooks to see if size affects the result.
Safety Precautions
- Pull carefully to avoid sudden slips that might cause someone to fall or bump into something.
Questions to Consider
- Why does interleaving many pages produce so much friction?
- How does the number of contact surfaces affect the total friction?
- What role does friction play in everyday activities (e.g., walking, driving, holding objects)?
- Could lubrication between the pages reduce the friction and make the books separable?