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Podcasts & Activities
for Curious Kids & Their Grown-Ups

Experiment: Floating Rice – A Simple Friction Experiment

In The Very Hungry Black Hole, Mindy does some experimenting with mayonnaise to help the time machine slip through the time-space continuum more easily. By doing this, she is attempting to reduce the friction. This simple experiment does the opposite- it increases friction! Which helps you float a rice filled bottle in the air. Check it out…

 

Ingredients:

  • sheet of paper
  • plastic bottle
  • uncooked long grain rice
  • pencil, pen, chopstick or wooden skewer

 

 

 

 

Wow-to:

  1. Roll paper into a cone shape making sure the small end is small enough to fit into the neck of your bottle. Place inside bottle.
  2. Carefully start to pour rice into the cone. Start by filling the bottle about ¼ full. Then tap the bottle lightly on the surface of the table to settle the rice.
  3. Repeat previous step three more times, until the bottle is full to the top with rice.
  4. Remove the cone and give bottle a final tap to be sure rice is fully settled.
  5. Very firmly push your pencil into the center of the bottle and press it all the way down to the bottom of the bottle.
  6. Gently lift the pencil and watch as the bottle and all the rice lifts with it. If this doesn’t work the first time, remove the pencil and tap the bottle a few more times to settle the rice and try it again.
  7. What happened is that the grains of rice are packed so tightly together that the friction between the rice and the pencil is strong enough o hold the pencil in place, allowing you to pick up the whole bottle of rice with the pencil. Wowsers!