Hooked on Science: Seesaw candle

Learn all about the center of gravity by using a few items from around the house.

Materials

* Candle

* Knife

* Matches

* Darning needle

* 2 identical drinking glasses

* Dinner plate

Instructions

STEP 1: Using the knife remove some of the wax at the bottom of the candle, revealing the wick. Note: Make sure the candle is not narrow at the top. Your candle should be the same size at both ends.

STEP 2: Push the darning needle through the center of the candle.

STEP 3: Place the drinking glasses next to each other on top of the dinner plate.

STEP 4: Allow the needle to rest on the lip of each drinking glass. Make sure you leave enough room so the candle can seesaw between the drinking glasses.

STEP 5: Using the matches light both ends of the candle.

Explanation

Before lighting the candle the center of gravity was directly in the center of the candle causing the candle to balance. The dripping wax causes the center of gravity to shift from one side to the other side, creating a seesaw.

Jason Lindsey is a Science Outreach Educator with Hooked on Science. Check out his website "Hooked On Science" at hookedonscience.org for webcasts and experiments that might get you hooked on science. Send him your science questions at jlindsey@hookedonscience.org. More science experiments can be found at www.semissourian.com.