Tell us about yourself!
Tools and Supplies
Raspberry Pi Class
You can take the ball and the bottle for a dive to a depth of near 30m and down there you could easily insert the ball into the bottle. This is exactly what my diving instructor used to show me the effects of high pressure under water; he took a tennis ball with him and showed it to me at the bottom. When you return to the surface the ball recovers the original shape. No holes needed! :)
Simplest and Cheapest Arduino
Aeroplane from an Aluminium Can (and it flies too)
Miniature Guitar/Audio Amplifier