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Here's a Question!

Big Balloon, Small Balloon

Two balloons are inflated with air, one much more than the other. The balloons are attached to a piece of PVC pipe and a clothespin is used to pinch the small balloon closed. What happens when the clothespin is removed?

Announcer: Frostbite Theater presents... Cold Cuts! No baloney!

Joanna and Steve: Just science!

Joanna: Hi! I'm Joanna!

Steve: And I'm Steve!

Joanna: Here's a question for you...

Steve: Two balloons are inflated with air, one much more than the other.

Joanna: The balloons are attached to a piece of PVC pipe and a clothespin is used to pinch the small balloon closed.

Steve: What happens when the clothespin is removed?

Joanna: Does nothing happen?

Steve: Do the balloons jet off in opposite directions?

Joanna: Does the large balloon give air to the small balloon until they're about the same size?

Steve: Or, does the small balloon basically give its air to the large balloon?

Joanna: Pause the video now if you'd like to think it over before we show you what happens.

Joanna: Have you ever blown up a balloon and found it nearly impossible to get started but, once you did, it got easier as the balloon got larger? This means that the balloon is able to squeeze more when it's small than when it's large.

Steve: Since the small balloon is squeezing more, the air pressure in the small balloon is higher than the pressure in the large balloon.

Joanna: Air flows from high pressure to low pressure. So, when the clothespin is released and the balloons are connected, the air flows from the small, high pressure balloon, to the large, low pressure balloon, until the pressures equalize.

Thanks for watching. I hope you'll join us again soon for another question!

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