two questions that i would like answers

Salt water weighs more...woops. lol

 

yes but the gravity is different so weighting the fish would be different in frest vs. salt

 

look here is a better comparison with the hot air ballon.

the earth weighs X kg(including everything in its atmosphere).
you add a hot air balloon that weighs 300 kg, no atmosphere is lost

what does the earth weigh now? its weighs X+300kg.

 

How can you put one object inside air or water without any displacement? That's impossible.

 

only if you weighed the fish in the water(IE the scale is in the water and you are only weighing the fish not the whole system).

 

the air or the water isn't at the edge of the container, some is displaced but none is lost from the total system.

 

Iprefer rolled in batter and dipped in oil.....LOL


Who is calling Myth Busters????? I nominate Dellyjoe since it was his question...LOL

 

Air isn't in a container. It's everywhere. If air is moved, then it is displaced, which is my point. If you put an object in water or air the object is taking place of what was there before, moving, or displacing that water or air. Water may overflow if we add a bunch of rock to a system; same goes for fish. Air will move too, but obviously it's not literally going to "overflow" as that's not really possible either(it's a gas)...

 

haha. Good point Coraline. But I don't believe that was the question. The fish's weight is known. What about the entire system(10lb fish plus the supposed 500 lbs of fish tank)?

 

oh but air can be in a container.. CO2/O2/etc tanks, any gas thats heavier then air will not leave a container, a planet is a gas container of sorts.



YouTube - Ship floating on nothing! :: Physikshow Uni Bonn