Warm Air Rises (Making a Hot Air Balloon))

Hello, I'm Jared, back with some more experiments on the idea that warm air rises, and this one's going to be interactive, fun. We're going to make a hot air balloon using birthday candles. Tape, scissors, bundle of straws, and a plastic bag, and that's our hot air balloon. So first, we need to make our structural supports out of straws, and all I'm going to do is I'm going to need to attach straws together, and I'm actually going to use straws to do that. So I'm going to snip off a little section of straw. That's going to be my splice, and to make the straw fit, I'm just taking the scissors and slitting the ends of that straw so that I can more easily go into the other straws. Take another straw, roll it up, insert that. You're going to notice I have it fitted together. The next one, I'm going to insert this. Now I'm going to just measure it out so I have 40 centimeters on my meter stick here. Hold it up, mark where 40 is, snip the end, and now I have a one. Let's make another one. I have to join these together as an x, so I'm going to find the halfway point using my meter ruler. That's 20. Great mathematicians go with science. Take a little bit of tape, and now I'm going to form my x, and I'm just going to wrap the center of my x with the tape. So far, nothing tricky here. In fact, kids may be able to handle to do this, snipping straws, taping them together. You want to make sure it's stable. Now all I have to do is attach it to my bag. So I have my bag opening. I'm going to spread it, and what I am going to do here is just wrap the little bit of the bag around my straw. Tape. You don't want to go crazy with the tape. The lighter this bag balloon is, the better. Okay, go to my opposite opening here. More tape. A little bit. Slide it up to the end. All I'm doing is catching the bag and the straw with my tape and wrapping it around the end. Almost there. Stretch my bag opening out. I just attached the last two. Obviously, a real hot air balloon is tethered by ropes. This is just going to hold our bag open. Last piece of tape wrapped around the straw. A little bit of straw hanging over where I wrapped tape around, and you will see I now have my hot air balloon structure. Thanks for watching. Back with part two for our hot air balloon experiment using birthday candles. What candles to use? We want to use the smallest candles possible. You can see I have two here. We want to go with the smaller one. These are actually two and a half inches by a quarter inch, and all I have is a four by four inch square of aluminum. It's just aluminum foil cut out, and this is the tricky part. I have to attach my candles to my aluminum, and to do that I'm going to heat up the end of this candle until it's soft and pliable, and then attach it to the tin foil. Notice I have my safety glasses on for protection, so I'm going to heat the end here using my burner just until it's soft, and I'm going to hold it until it secures. That's one. You don't want to burn your fingers. Two. If they pop off, no big problem. You can simply attach them again, and they probably will fall off at one point or another. There's three. There you go. See it fell. If you don't hold it long enough, it will fall over. You can blow on it a little bit. They're holding nicely, and number four, and I'm going to let that dry. I have it all complete. The next part, and we want to make sure it's totally, the wax is dry and set up, we need to attach it to our balloon. We made our burner previously. We made our balloon. Now it's time to put them together, so we're going to flip this over. You want to be careful. The candle should still stay attached to the aluminum foil. It's the beauty of wax, and very carefully, I'm going to attach this aluminum foil to my straw structure just with some tape. Again, don't go crazy with the tape. We want this to be as light as possible so that we have lift to our balloon. A lot of safety features to think about here that we're going to highlight later, but it's really a neat experiment for kids to see that warm air rises. I have it attached, and you can see the candles through the bag, and now we're going to fly this thing. I'm going to just peek up under here so I can see what I'm doing. It's a little bit awkward trying to get this on camera. Once I get, I got them lit, and what's going to happen is that those candles are going to start to heat the air up, and that warm air is going to fill this bag. I'm going to let it set on the table, and this is where you have to have patience. Right now, that warm air is filling the bag, just like a hot air balloon. Hot air balloon uses giant burners that shoot that hot air up in. This is using birthday candles, so it's going to take some time, but you're going to eventually see the bottom start to lift off of the table. That warm air is rising. Those air molecules are spreading out. They're becoming less dense, and you can see we have some movement here. Houston, we don't quite have liftoff, but we have movement, and it's pretty cool. When you see this thing take off, it's going to rise to the ceiling because warm air rises. We have movement here. I don't want to lift it, and you see this thing starting to take off. The air currents in the room are going to push this thing all over, but that is a hot air balloon if I've ever seen one. It's not going to lift me up. You can see as it bangs the ceiling, it pushes some of the hot air out, and you'll see it drop a little bit. It's going to float over here. Now, if I were doing this in an auditorium or a gym where the ceilings are 40 feet high, you're going to want to tether this. The cool thing about this is the wax is only going to on the tin foil. If the candle were to break loose and fall, it would blow itself out. That's the beauty of using birthday candles. Now, this is a cool birthday cake. Sing happy birthday. The magic is going to happen when I blow these candles out, and you'll watch as the air cools down. It's going to sink, so here we go. It's losing its lift. The cold air does not want to rise. It wants to sink. It's still filling the bag. You're going to see the bag start to collapse as the air cools down because cold air sinks, warm air rises. How cool is this? It's science. Thanks for watching.