3 ms·

Is not "Down" with gravity, and "Up" against?

• cperciva 15y ago
  If you're neutrally buoyant, there is not gravity.
  • corin_ 15y ago
    Yes there is... Gravity is gravity is gravity. If I jump in the air does that mean there's no gravity while I'm going up?
    • radq 15y ago
      This is the fundamental difference between a fish floating in water and a person jumping up. http://i.imgur.com/nkwVc.png http://i.imgur.com/nkwVc.png In the second case, gravity acts on you even when you are going up, in fact it is what slows you down and then makes you start to fall.
      • corin_ 15y ago
        Yes they aren't identical situations, but you'll notice in your diagram that there is a downward force acting on the fish called "gravity", which is the point I was making - that gravity is acting on fish and humans regardless of what upward forces are also present.
    • jongraehl 15y ago
      Try to appreciate the sense in which his statement might be true before nitpicking. It's true that free-fall feels substantially different from floating underwater, or even lying on a soft surface (the last two are more similar subjectively than free fall - the force resisting gravity is spread over your body).
  • 5l 15y ago
    But the swim bladder which makes them neutrally buoyant will give them an "up" and "down" sensation.