 Welcome back to Kids Fun Science. My name is Ken. Today's experiment is the Rockin candle. As always, adult supervision is required. What you need for this experiment is a candle, a nail, a lighter, two glasses, and some adult supervision. We're going to start off with a candle and expose the wick on both ends. So you have to kind of carve out the bottom end so it has a wick there. Then you're going to put a hole halfway down the middle of the candle and then the same size to be able to get a nail in there so it goes all the way through. And then you're going to take that nail about halfway through and you're going to balance it on two glasses so the candle can be on its own but not hit the glass itself. So you want to kind of adjust that. And now you have wicks on both ends of the candle and then we're going to light it from there. Now with adult supervision, you're going to light one end of the candle and then you're going to light the other end of the candle and your experiment will be ready to go. This experiment teaches us about combustion and Newton's third law motion. A candle that's balanced between two pair of glasses will rock or seesaw up and down on its own. This motion continues as long as the candle continues to burn. One side of the candle starts out heavier than the other. The motion of the candle will act as an equalizer and the mass on either side will pivot from one point to another. The candle moves in response to the forces acting on it, trying to equal out on each side. The combustion reaction that turns the candle wax into carbon dioxide gas and water vapor, making the burning end of the candle lighter. If one end of the candle burns more quickly than the other, the lighter side of the candle moves up. The lower side of the candle will angle such that the flame melts the wax, causing it to drip down. This not only lessens the mass at the end of the candle, but forces the dripping wax actually pushes the end of the candle up. This is Newton's third law of motion, which states for every action there's an equal or opposite reaction. Just make sure with the candle that you have an adult present, as the candle will start teeter-tottering back and forth as it loses that mass. So it's really cool at the same time you want to be safe and make sure you watch what's going on. I have a cutting board underneath here for the hot wax, and as you can see it's starting to lose its mass on one end and it's pulling back up on there to start to get that teeter-tottering or rocking the boat up and down. So now it's about even and it's starting to lose a little bit more and we're going to start seeing this thing move in a little bit. What's cool about this experiment is every time I do it's a little bit different because every candle seems to burn a little bit different. You can see here on the right hand side the wax is completely burnt out on the big end on the top part, so it's getting ready as it loses that mass on the top to start making that seesaw up and down rocking the boat effect. You want to make sure your nail is not too tight in there because it'll just roll the nail. You want to candle the rock up and down on itself. Here it goes. We're starting to see the wax starting to drip out there and you start to get a little bit more of a rocking motion here as the weight is altered. As you can see the wax drips about one or two on the left and then a whole bunch drips out on the right and that's what gets your weight transferred the mass going back and forth and getting that seesaw action. Like I said, try different candles when you do peel off the other end to get to the other wick. Make sure you don't take off too much of the candle. You want to have that weight there that's going to help it rock. Here you're ready to lose that last little piece right there. I think it's going to go a little bit farther there. It's pretty pretty cool. Well I hope you enjoyed this video. Remember to click thumbs up and to subscribe. Thanks for watching!