• Small coffee can
  • 1 marble
  • How can I make the marble stay in the can while having it turned upside down and off the surface of the table?
  • The marble cannot be touched.
  • The marble must stay in the can for at least two seconds.
  • Place the can upside down on the surface of a table.
  • Place the marble under the can.
  • Move the can in a rapid circular motion, making certain the marble rotates around the inside of the can. While doing this procedure, lift the can straight off the table.
Why does the marble stay in the can? Due to Centrifugal and Centripetal force, the marble remains in the can.

Centrifugal force: The force that tends to impel a thing or parts of a thing outward from a center of rotation.

Centripetal force: The force that is necessary to keep an object moving in a circular path and that is directed inward toward the center of rotation.