Praxis: A Deep dive up in the air
By Patty Rooks - Praxis on April 13, 2019.
praxis@praxismh.ca@PraxisMedHat I have been busy this week working on some air and aerodynamics activities for some workshops Praxis will be hosting. As I dive deeper and deeper into the science behind air, I am truly fascinated! I never thought that something we cannot see, feel, taste or really touch could be so interesting. I thought I would share one of the activities with you this week so you can better understand what I am talking about. It is a bit tricky. Let’s get started! *Remember to ask an adult before you do this experiment. Materials – two empty 500 mL clear water bottles – two balloons – nail – two science volunteers Procedure 1. You will need to prepare the materials BEFORE your volunteers arrive. 2. Take one of the empty 500 mL water bottles and stretch a balloon over the mouth of it. The balloon should be hanging down into the bottle and the neck of the balloon around the rim of the water bottle. 3. Have an adult help you poke a hole in the bottom of the second empty water bottle. 4. Similar to before, place the balloon inside the bottle and have it ready to blow up. 5. Hand one bottle to each of your science volunteers. 6. On the count of three, have them blow the balloon up. 7. Observe. 8. What happens? What is going on? The volunteer that had the balloon in the bottle with the tiny hole in it should have been able to blow it up with no problem at all. I hope the other helper did not pass out trying! In the first bottle, it would have been a lot easier to blow the balloon up because of air and the space it takes up. Let me explain this a bit further. In the bottle with no hole in it, three is air in the bottle and around the balloon. When you try to blow the balloon up it will not happen because of the air in the bottle already. There is nowhere for the air to go – it is taking up space even though you cannot see it. In the bottle with the hole in it, air is allowed to escape out that hole, even if it is a tiny one. As you blow into the balloon, it pushes the air out and there is room for the balloon to expand. This is a bit tricky to understand because you cannot see air. Trust me, it is there, and takes up space. Something else cannot move into the space air occupies, as you just learned! Patty Rooks is senior scientific consultant at PRAXIS, “Connecting Science To The Community.” Contact Praxis at praxis@praxismh.ca, http://www.praxismh.ca, Tweet or follow us @PraxisMedHat, or friend us on Facebook. 21-20
