Physics Exercises/Equilibria

  1. Stacked half-balls
    How many half-balls can be placed on top of each other? The picture shows three. Can you add one more?
  2. What shape take 2 equal soap bubbles when they touch each other? What happens when the bubbles have different volumes?
  3. A foil balloon is made of 2 disks of thin, unstretchable, nylon film welded at the edge. What shape takes the inflated balloon?