Multiple choice general knowledge

The sound you hear when you crack your knuckles is actually the sound of nitrogen gas bubbles bursting.

  1. True

  2. False

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The cracking sound comes from bubbles FORMING in synovial fluid, not bursting. When you pull joints, pressure drops and gases (mostly nitrogen) come out of solution to create bubbles - the 'pop' is cavitation, not bubble collapse.