2004 HS Photo Contest Pictures
2004 High School Photo Contest Winners
This is a picture of a balloon the moment after it was popped underwater. The two black bars at the bottom of the picture are weights that are resting on top of a needle that has been run through the tail of the balloon's tied end. Before the balloon was popped, the air pressure inside it was equal to the pressure exerted by the surrounding water and the balloon itself. Equilibrium is maintained until the needle pierces the balloon, causing it to rip apart and leaving the air it contains to push against the water. As seen, the gas separates into hundreds of tiny bubbles as it begins to expand and rise through the water.