I'll try to explain displacement, which is the property behind what makes a boat or ship float.
If you set a large bucket in a big empty pan and filled the bucket all the way to the very top with water, you couldn't put anything else in the bucket without water overflowing out of the bucket and into the pan.
If you lower a rock into the water, the rock will displace, or move out of the way, the same volume of water as the rock has. That water will end up in the pan.
If you weigh that displaced water, it will weigh less than the rock. That is why rocks sink. They weigh more than the amount of water that they displace.
A boat or ship has something a rock doesn't have. A huge volume of open space inside. If you had a boat carved out of rock that was solid, and one carved out of the same rock that was hollow, the hollow one would float.
If you put a model boat that weighs the same as the rock, into the full bucket of water, the boat would float, but some of the water would be displaced. Water would be pushed over the sides of the bucket and into the pan. When you weigh the water in the pan, this time it would weigh the SAME as the boat.
Technically, it's not the weight of the water or boat, it's the mass, but don't worry about that little detail.
The more weight you add to a boat or ship, the deeper into the water it goes. That also means that more water is being displaced. If you add 10 pounds to a boat or ship, it immediately sits just a tiny bit lower in the water and displaces 10 pounds more water out of the way.
So, a 1,000 pound ship would displace exactly 1,000 pounds of water. That is the definition of displacement. As long as the hull displaces more water (in weight, pounds or tons) than it weighs, the vessel will float.
If you set a large bucket in a big empty pan and filled the bucket all the way to the very top with water, you couldn't put anything else in the bucket without water overflowing out of the bucket and into the pan.
If you lower a rock into the water, the rock will displace, or move out of the way, the same volume of water as the rock has. That water will end up in the pan.
If you weigh that displaced water, it will weigh less than the rock. That is why rocks sink. They weigh more than the amount of water that they displace.
A boat or ship has something a rock doesn't have. A huge volume of open space inside. If you had a boat carved out of rock that was solid, and one carved out of the same rock that was hollow, the hollow one would float.
If you put a model boat that weighs the same as the rock, into the full bucket of water, the boat would float, but some of the water would be displaced. Water would be pushed over the sides of the bucket and into the pan. When you weigh the water in the pan, this time it would weigh the SAME as the boat.
Technically, it's not the weight of the water or boat, it's the mass, but don't worry about that little detail.
The more weight you add to a boat or ship, the deeper into the water it goes. That also means that more water is being displaced. If you add 10 pounds to a boat or ship, it immediately sits just a tiny bit lower in the water and displaces 10 pounds more water out of the way.
So, a 1,000 pound ship would displace exactly 1,000 pounds of water. That is the definition of displacement. As long as the hull displaces more water (in weight, pounds or tons) than it weighs, the vessel will float.
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