Originally posted by EmLasker since it's made of metal which have a much higher mass density than water.
anyone with last name Einstein, Newton, Bohr, Becquerel, Heisenberg, please answer.
…since it's made of metal which have a much higher mass density than water.
Yes -but remember it has many air-filled departments and there is much more volume of air in a ship than metal (unless it is sunk of course) and air has much less density than water and this makes the overall density of the ship i.e. its total mass divided by its total volume (including the volume of air it contains) is less than that of water which is why the ship floats.
Originally posted by EmLasker i asked this Q after seeing my poop floating in the toilet
Well considering poop floats as you have discovered, then it is the poop onboard the ships that make it float. In the case of the titaninc, the ice berg scared the poop out of them. They washed it all off the deck and then sank. Luckily there was some bird poop on the life boats, or they would have had similar fate. Exploring concepts of science such as this is what enables humanity to continue to advance at an exponential rate.