Topic: I don't get how its possible for a cruise liner to float
No1phD's photo
Thu 02/28/19 02:54 PM
To this day it's still boggles my mind how a ginormous ship. Weighing thousands of tons.. stays afloat... I can take a piece of flat sheet metal drop it in some water and it sinks to the bottom...lol.. just doesn't make a lot of sense that's all I'm saying... same thing with how do planes stay in the air.. like I get the physics behind it!!!.. it still doesn't make any sense..lol

jimboinVTA's photo
Thu 02/28/19 03:53 PM
With a ship it is about the amount of water it displaces. A flat sheet of iron has no capacity to displace anything. It might raise the water level but cannot displace water the way that the hull of a ship does.
As for the planes, I guess looking at birds could give you some incite.

ivegotthegirth's photo
Thu 02/28/19 08:33 PM
It the same reason why huge whales, the largest mammals on earth that can eat tons day only have a throat opening a couple of feet across...

Tom4Uhere's photo
Thu 02/28/19 10:44 PM

To this day it's still boggles my mind how a ginormous ship. Weighing thousands of tons.. stays afloat... I can take a piece of flat sheet metal drop it in some water and it sinks to the bottom...lol.. just doesn't make a lot of sense that's all I'm saying... same thing with how do planes stay in the air.. like I get the physics behind it!!!.. it still doesn't make any sense..lol

You say you get the physics behind it but if you did, you wouldn't be asking this question.

The ship floats from buoyancy and displacement.
Water also has a viscosity.
If you were to introduce air bubbles under a ship, it would sink.
Did you know there are mountains and valleys on the surface of an ocean?
In areas where there is more water (submerged valleys) the water lifts and when there is less water volume (submerged mountain) the water is pulled downward.
The weight of the ship is relevant to the size of the body of water and the empty space inside. If you were to fill all voids in that ship with water or something heavier than water - it would sink.

A plane can fly because of differences in what is called 'lift'.
Air rushing over the wing causes a low pressure area that is less than the atmospheric pressure pushing down on it.
The wing and the plane which is attached to it, moves towards the area of lower pressure. Nothing special is pushing the wing higher.
That action is the wing being drawn upwards.

Freebird Deluxe's photo
Thu 02/28/19 10:48 PM
Fill your sink and put a heavy bowl in, thats it on a smaller scale,
Warning do not try to fly the bowl it is the wrong shape

Tom4Uhere's photo
Thu 02/28/19 11:06 PM

Fill your sink and put a heavy bowl in, thats it on a smaller scale,
Warning do not try to fly the bowl it is the wrong shape

Well, technically, that bowl might fly pretty well if you can put enough thrust into it.
Plus, an inverted bowl that flies pretty good is also known of as a Frisbee.

Ever skip a stone across a pond?
I once told a woman to pick any stone I can fit in my hand and I would skip it at least once.
She did and I skipped it.
Its not about the weight or buoyancy of the stone.
Its about the speed of its flight, the angle of its contact and the surface tension of the water.

itsflat's photo
Fri 03/01/19 12:36 PM
Edited by itsflat on Fri 03/01/19 12:43 PM
https://goo.gl/images/bMyk1Q

Totage's photo
Fri 03/01/19 12:56 PM

To this day it's still boggles my mind how a ginormous ship. Weighing thousands of tons.. stays afloat... I can take a piece of flat sheet metal drop it in some water and it sinks to the bottom...lol.. just doesn't make a lot of sense that's all I'm saying... same thing with how do planes stay in the air.. like I get the physics behind it!!!.. it still doesn't make any sense..lol


Beep! Beep! Richie! They ALL float down here!

IgorFrankensteen's photo
Fri 03/01/19 04:14 PM

To this day it's still boggles my mind how a ginormous ship. Weighing thousands of tons.. stays afloat... I can take a piece of flat sheet metal drop it in some water and it sinks to the bottom...lol.. just doesn't make a lot of sense that's all I'm saying... same thing with how do planes stay in the air.. like I get the physics behind it!!!.. it still doesn't make any sense..lol


If the ship was a flat piece of metal, it would sink too.

Dent your sheet metal deeply enough, and it will displace water, and float as well.