Behind the water bottle flip

The water bottle flip has entered all of our lives whether we like it or not. Here’s why it works.

Nina Elkadi, Print Editor-in-Chief

“I am the one don’t weigh a ton / Don’t need a gun to get respect up on the street*,”

If these lyrics mean anything at all to you, there is a good chance that you are familiar with the infamous water bottle flip. If they mean nothing to you, chances are you have seen your peers attempting to flip a plastic water bottle in an effort to stick the landing. It has recently taken social media by storm, and Dominic Audia, physics and principles of engineering teacher, has an explanation for this satisfying phenomenon. Be cautious, it isn’t as simple as it may appear.

Imagine an ice skater spinning in a circle. When they tuck their arms into their chest, it may appear that they are spinning faster — because they are. Now, think about the water in a plastic bottle. Initially, the water is concentrated at the bottom. When it spins in the air, it becomes spread out, causing it to slow down. So, what’s the key to preventing the bottle from stopping in mid-air?

“Part of the trick of doing this is to grab [the bottle] by the top and to generate a high angular velocity as quickly as you can,” Audia said. “You’re trying to whip it.”

There does seem to be a “trick” to the flipping, and Sam Sunderland ’19 is considered a “pro water bottle flipper” by his friends.  Audia agrees with Sunderland in that the perfect amount of water to incite the perfect flip is about ¼  – ⅓ of the way full.

“The rotational inertia is equal to the radius squared times the mass of the water. Changing the radius [of the water] has a big effect on it, because it’s squared,” Audia said. “The mass is also another factor, so gravity is acting on the center of the mass. If you adjust the weight correctly, then it should land in the right spot.”

For Sunderland, water bottle flipping is less about the physics and more about the satisfaction he receives from a successful flip.

“I need to stop. It has become too much of a habit,” he said. “My mom, she banned water bottle flipping. She’s sick and tired of the sound.”

From now on, water bottle flippers should always keep in mind how much physics goes behind each flip.

“There’s a physics behind it, but there’s also an art,” Audia said.

*Ultimate by Denzel Curry