Want to do a fun and simple air pressure experiment? You just need a few basic supplies to make this sprink-o-lator!
Today we’re welcoming back Curt Nelson from Make a Kidnection, where he uses stories to make science fun!
The balloon in a bottle experiment demonstrates the strength of the air pressure all around us. Because we’re so used to the air pressure pressing on our bodies, we don’t even notice it. But when your kids see that same air pressure keeping an untied balloon inflated – that’s pretty cool.
Think of how hard you have to blow to inflate a balloon. The air pressure needs to push just as hard to keep the balloon inflated. And that same air pressure is pushing on our bodies all the time!
And that’s just the first part of the experiment. Then you fill the balloon with water and release the air pressure, and the balloon squeezes the water out in a nifty fountain.
What’s the purpose?
I’m a former high school science teacher and a mechanical engineer, so I love science activities, especially when they relate to solving an actual real-world problem. (That’s basically the definition of engineering – science applied to real-world problems.)
So in this case, what real-world problem could you solve with a balloon-in-bottle that shoots water?
Well, what if your dragon was traveling through a barren desert and needed a portable drinking fountain?
That may be a bit of a stretch (balloon pun intended), but it does get kids thinking about how this principle could be applied to create something useful. See if your kids can come up with other ideas and share in the comments below.
What you’ll need
1) A plastic bottle like those pictured above. Any size will work as long as the diameter of the opening is small enough to stretch a balloon around.
2) A couple balloons – 5″, 9″, 11″, 12″ or 16″ balloons will all work. You only need one balloon, but if your kids want to keep playing with the sprink-o-lator, they’ll have to replace the balloon every couple times. (Screwing the lid on and off tears the balloon up.)
3) A thumbtack or pin to poke a hole in the bottle and the lid.
See the video below for a step-by-step demonstration of exactly how to do the experiment.
The fun science video
Bob the Dragon and I shot a short video to set the stage for your kids. It’s fun and silly, but also gives them a reason to do this experiment.
Check it out with your kids, and then keep watching while I show you exactly how to make a sprink-o-lator:
The bonus video
Then, to reward your kids for doing such a great job on this activity, show them this bonus video featuring Bob the Dragon’s favorite animal jokes. It reinforces the idea that science is fun and scientists have a good sense of humor.
Stay in touch with Curt
Curt is a former science teacher and school assembly presenter. Now he (and Bob the Dragon) make learning science fun at MakeAKidnection.com. You can also follow Curt and Bob the Dragon on YouTube. They release new experiments about every other week!