Kate's Corner: Floating bottle of rice

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BRIDGEPORT, W. Va. (WDTV) - In this edition of Kate's Corner we are going to use science to lift up a bottle filled with rice with just a pencil. It won't take years but actually just a few seconds.

First we have to fill up your bottle with rice. Easiest way to do this is with a funnel. Now fill it up all the way to the top. Next, take your pencil and put it through the rice. Now try to take your pencil back out. The bottle comes with it. Why can you lift up the bottle by just putting a pencil in?

Well, when you put the pencil in the bottle of packed rice, it took up additional space. The rice then had a difficult time moving up the neck of the bottle because it is not a fluid. Without the rice being able to compensate for the space that the pencil takes up, the rice has very little space to move so it presses on all surfaces. This wedges the pencil in. The resistance you feel when you try to pull the pencil out is friction. The friction is strong enough in this case to hold the pencil in place.

You can try this with a friend. Fill your bottle all the way to the top and leave theirs only filled just a little over halfway.