# Weird Science - Balloon in a Bottle - Hawaii News Now - KGMB and KHNL

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### Weird Science - Balloon in a Bottle

Honolulu (HawaiiNewsNow) - Dr V. and Taizo blow up some fun as they visit the children at Shriner's Hospital for Children.

Dr. V Show: Balloon in a Bottle

Things you need:

• 2 clean water/soda bottles
• Metal skewer or power drill
• Balloons

The experiment

Please perform this and all experiments under the supervision and with the assistance of an adult. Stretch the neck of the balloon over the bottle opening and push the rest of the balloon into the bottle. Put your mouth around the bottle and try blowing up this balloon. Are you able to blow up the balloon? Ask an adult to make a small hole in the bottom of the other bottle. Take another balloon and do the same thing. Try blowing up this balloon. Are you able to blow up the balloon this time? If you're able to blow up the balloon in the bottle with the hole in it, try covering the hole with your finger as you blow one more time into the balloon. When you take your mouth off the bottle, what happens to the balloon? Now take your finger off the hole. What happens to the balloon?

How does it work?

Why can't you blow up the balloon in the first bottle? It's not that your lungs aren't strong enough; it's that there is already air in the bottle that's taking up space. There is no more room for you to fill the balloon up with more air. Your lungs would have to be strong enough to compress the air to be able to fill the balloon up.  You should be able to blow the balloon up in the second bottle with the hole in it. The hole allows the air in the bottle to escape and make space for the air you're blowing into the balloon. When you cover the hole with your finger, you don't allow the air back into the bottle. So if you cover the hole when your balloon is full of air, it stays inflated after you take your mouth off the bottle. Although the balloon wants to deflate and push the air out, it can't, because there is no air to replace the air getting pushed out of the balloon. When you uncover the hole, you're allowing the air back in to the bottle, so the balloon is able to deflate.