Warm and Cool Balloon

Most of us have inflated a balloon, but have you ever noticed the difference in temperature between an inflated balloon and a deflated balloon? “Science Guy” Jason Lindsey with Hooked on Science says there is a difference, and it’s all about science.

 

Supplies

Balloon

Instructions

STEP 1: Inflate the balloon and then quickly feel the outside of the balloon.

STEP 2: Deflate the balloon and then quickly feel the outside of the balloon.

 

Explanation

The inflated balloon feels warm, while the deflated balloon feels cool. As the air is released through the small opening of the balloon, the temperature drops in a process called the Joule-Thompson Effect. It requires energy to force the air through the small opening. The removal of this energy results in a drop in temperature. Go to hookedonscience.org for more experiments that might get you “Hooked on Science.”