We gonna put in some shaving cream to see what will happen. Check out the video to see. I’ll also explain it below.
In the cream there’s alot of air trapped inside. Like small bubbles. When the pressure surrounding decreases, the air trapped inside will expand. This causes the foam to grow. During this time, some air will escape from the foam so when letting air in and the air go back to it’s normal size it will be smaller since it did lose air.
It was over expectation that it would grow so fast and much. A great and fun experiment.