Truth matters. Community matters. Your support makes both possible. LAist is one of the few places where news remains independent and free from political and corporate influence. Stand up for truth and for LAist. Make your year-end tax-deductible gift now.
The Popping Sound Cracking Knuckles Make Continues To Intrigue
Listen
0:28
Listen to the Story
NOEL KING, HOST:
Good morning. I'm Noel King with the answer to a mystery that has puzzled scientists and kids for years. When we crack our knuckles, why do they make that popping sound? A grad student in France, Vineeth Suja, was cracking his knuckles in class and thought he could figure it out. He worked up a series of math equations, and, well, it's complicated, but there are little bubbles in your joint fluid. And when you crack your knuckles, the sound you hear is the bubbles popping. It's MORNING EDITION. Transcript provided by NPR, Copyright NPR.