Multiple choice general knowledge science & technology

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
A Correct answer
Explanation

The cracking sound from knuckles is indeed caused by gas bubbles in the synovial fluid collapsing. When you pull or bend your finger, you create negative pressure that causes dissolved gases (mostly nitrogen and carbon dioxide) to form bubbles. When these bubbles burst, they create the characteristic cracking sound. It takes about 20 minutes for the gas to redissolve, which is why you can't crack the same knuckle repeatedly.

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