Actually, weight = mg - ng | n = the mass of the medium displaced. In our case it is the same substance and volume.
So...
weight of a water in water = mg - mg = 0;
I did this math earlier, thanks for reading.
Ok I'm back.
You are still wrong. The mass of the second m would be much greater than the first, thus you would have negative weight. This of course is going by what you said.
Now on to the other part that you are wrong. Saying the whole ocean would float around, so what medium is the whole ocean in that is the same mass as the whole ocean to cancel out the whole oceans weight?
Perhaps you can explain how the second m is smaller? This should be rich...
Please provide an example of a single molecule of ocean water that is not in a water medium. If the ocean entirely consists of such molecules it is entirely within a water medium. Therefore the ocean is weightless.
1 gallon of water in a pool that has more than one gallon of water in it. 1 gallon does not mass the same as 1,000 gallons.
You cannot look at a single molecule of water and then use its features to look at the whole ocean.
To find the whole ocean’s weight take the whole oceans mass and then multiply it by gravity.
You need to look up the word medium. According to you, my pop can is in a pop can medium and there for should float.