Activity: Fluidity


  • To discover that air has fluid properties and takes up space.


  • A glass
  • Dry handkerchief or tissue
  • Large deep bowl of water


  • Push the dry handkerchief into the bottom of the glass so that it will not fall out when the glass is turned upside down.
  • Turn the glass upside down and holding it vertically, push the glass into the jar of water until completely covered.
  • Now, lift the glass straight up and out of the water.
  • Turn it right side up.
hand pushing a hankerchief in a glass    hand pushing a hankerchief in a glass in a bowl of water    hand removing a hankerchief from inside a glass


  • The handkerchief is completely dry.


  • Why isn¬ít the handkerchief wet? (The air took up space and kept the handkerchief from getting wet).


  • The air inside the glass took up space which is a property of fluid.