Jimmy does a cannonball into the swimming pool. After surfacing and floating for a few seconds, he observes something interesting. He notices that if he takes deep breaths his body seems to float more. Also he notices that he sinks into the water after he releases his breath. Explain why this is happening to Jimmy.
Oxygen (air) is lighter than water so if you take a deep breathe you'll float. Think of it like a balloon that someone has blown up. It floats on water.
