How do massive ships float

When I jump into a swimming pool, I sink like a stone unless I flail about wildly, but when the USS Enterprise aircraft carrier — which is just a tad bigger and tad heavier than I am — jumps into the ocean, it floats with no effort whatsoever. Some big, heavy things — like the USS Enterprise — float in water. Everything on Earth, whether on the surface or under water, has the weight of everything higher up pushing down on it. Yes, right now as you read this, the weight of all of the air above you, right up to the top of the atmosphere, is pushing down and in on you.

The resulting force is about Water is relatively heavy — go down just 30 feet and the weight of the water per square inch on your body will equal the weight of the hundreds of miles of air above you. The answer is simply that the water below you is pushing up.

There you are, underneath the surface in a swimming pool. In addition to buoyancy and displacement, there are several other factors that help cruise ships remain on the water's surface. To achieve buoyancy, a ship must be made of lightweight, sturdy materials which are denser than water, such as extra-strength steel. Additionally, those lightweight materials need to be used in a design which allows them to displace their weight in water before they submerge.

Most of that design is implemented in the hull which is the body or shell of the ship which sits below the main deck and pushes the water out of the way and allows the vessel to float. Through years of trial and error, engineers have found making the hull rounded, wide and deep helps disperse the weight of the ship across the body of the ship.

Large cruise ship hulls are shaped like the letter "U. Just staying afloat and cruising smoothly isn't enough; a cruise liner's hull design must also protect the people inside against obstacles like icebergs, reefs and sandbars which could rip apart the ship's outer layers. To prevent a major catastrophe , shipbuilders typically use extra-strength steel and build their ships with double hulls meaning one hull inside the other as an extra precaution.

Cruise ships also have bulkheads which can help them stay afloat in case of major damage. These watertight dividers are installed throughout the interior of a ship and can be closed to seal out water rushing in through a damaged hull. Limiting the water inflow can ultimately keep the ship from flooding and sinking.

As of , the biggest cruise ship in the world measures about feet tall, and even the average cruise ships still have impressive height. So what keeps them from tipping over in the water? The answer is, again, in the hull design. It depends on the type of boat, but damage to a ship can impact its ability to float.

The absolute maximum number of people is 6,! Hey there, Wonder Friend Mystery! A lot of people thought the Titanic was unsinkable, and unfortunately there were other things that affected its ability to stay above water.

Thanks for sharing your comment with us today! Hey there, Wonder Friends Beaux and Kenny! Thanks for sharing all the cool new things you've learned about boats, buoyancy and matter! Great question, Ryan M! Today's Wonder asks that same question-- how interesting! It's all about displacement, or how much water is moved when something is placed on top of it!

A rock is tiny and heavy, and not much water is displaced when you drop it in the water-- it sinks! However, a boat, when built correctly, displaces a lot of water because of its size. We know it can be tricky at first, but give the Wonder another try-- we know you'll get the hang of it! You're quite right, Wonder Friend Hunter.

That's the issue with ships-- they can float, unless they hit something. We're so glad to hear it, Bob! Thanks for visiting us today! What was your favorite part of today's Wonder? We're glad you're here today, Wonder Friend Pink!

We like using context clues to help us understand new or big words! Great guess, Hunter! We learned about buoyancy, which relates to the sinking of the Titanic. Great point, Patrick! The very first boats were shells-- even hollowed out logs tied together with reeds! We're so glad you're here today! Thanks for visiting us today to Wonder about buoyancy, Mrs. Roberts' Class! Have a marvelous Monday! Good morning to our Wonder Friends in Mrs. Plunkert's Class!

We learned about a term called displacement, which is hard to see with our own eyes. That's because water is fluid, or always moving. But displacement describes what happens when we put anything in water. Think of when you draw a bath. If you marked the waterline of the bathtub, and then got into the bathtub, you'd see the water rise. That's displacement! We are so glad you learned a new thing or two with us today.

We hope your day is float-tastic! Thanks for sharing your comment, Kenneth V! We're so glad you enjoyed today's floating Wonder-- we sure learned a lot!

The pufferfish sounds really cool, thanks for letting us know what your guess is! Hey there, Wonder Friends in Mrs. Hess' Class! We're so excited that some of you have been visiting us lately-- even on the weekends! Many believe Egyptians were the first to build ships, but even before then, people would create boats out of logs and bundles of reed. We bet you can find out some more information about the very first boats with some help from your librarian!

We're so proud of you! We're glad you learned something new with us today, Joaquin! Hess' class! Hey there, Wonder Friend Alvaro! The Titanic was believed to be unsinkable, which is why it's an incredibly tragic story. When the ship hit the iceberg, it damaged the vessel and its ability to safely float. We Wonder what book you're reading? It sounds great! Some Wonder Friends here at Wonderopolis have been on boats before We Wonder if you have traveled by boat?

You can do aluminum foil boats and put pennies in them and see if it sinks. I put pennies in a boat and I am seeing if it will float for 24 Hours. That's a neat idea, austin!

Thank you for sharing it. We hope you'll visit Wonderopolis again and let us know how your project goes! We are excited for you to embark on a Wonder Adventure all about boats! We suggest you visit your library to do research online and in books to find ideas!

You could even ask your librarian to help you begin! We are undergoing some spring clearing site maintenance and need to temporarily disable the commenting feature.

Thanks for your patience. Drag a word to its definition. You have answered 0 of 3 questions correctly and your score is:.

Want to add a little wonder to your website? Help spread the wonder of families learning together. We sent you SMS, for complete subscription please reply. Follow Twitter Instagram Facebook. How do boats float? What is displacement? Can you build a toy boat that will float? Wonder What's Next? Try It Out Ahoy matey! If so, be sure to explore the following activities with a friend or family member: What kinds of things float?

What things tend to sink? Make a list of things that float and sink and compare and contrast the items on your list.

What do the things that sink have in common? What about the things that float? Does that match up with what you learned in today's Wonder of the Day? Don't limit yourself to things in the water either! Can you think of things that float in the air? What about clouds? Have fun brainstorming! Ready for some bathtub fun?

Pick out one of the following crafts and make your own homemade boat! Is it seaworthy? Does it float? Test it out against some non-floating objects, such as rocks, to see firsthand the principles discussed in today's Wonder of the Day! Are you familiar with the story of the Titanic? You probably are. You may have even seen the movie that was made about the famous oceanic disaster. Did you know that the Titanic was called the "unsinkable" ship?

Can you imagine that? They sure were wrong, weren't they? Just about anything can be made to sink. Do some research to learn about the most buoyant things on Earth. Some things just seem to float really well. Think of a ping pong ball, for example. Can you imagine it sinking? Probably not unless there was a hole in it. If you have a ping pong ball, test it out. Will it sink on its own? What about if you put a small hole in it?

What do you have to do to make it sink? Can you find any other items that are almost unsinkable? Share your findings with your teachers and classmates at school! Did you get it? Test your knowledge. What are you wondering? Wonder Words float lazy awesome downward gravity beautiful peaceful collection homemade heavier battleship ancient scientist designed specifically displacement buoyancy disappointed Take the Wonder Word Challenge.

Join the Discussion. Vanessa Mar 14, Thank u 4 this article. It helped me a lot and I will visit it more in the future. John Ryan Dec 4, Daeus Nov 13, Nov 13, And we like our Wonder Friends. Thanks for taking the time to comment, Daeus! Gio Nov 2, Nov 4, Anonymous Jan 6, Liam Sep 16, Thanks for writing nice comments to everyone, your website is the best learning site.

Aw, Daeus! You're making us blush! Thanks for stopping by, Wonder Friend. Sep 16, You're welcome, Liam! And, thank YOU for sharing your love for Wonderopolis! Jaxon Oct 21, Thanks so much this helped so much for my science fair project. Nov 12, You're welcome, Jaxon! Did you build a boat? Liam Sep 10, Thanks so much for the help i am doing a project so this means a ton.

Sep 10, We sure hope your project goes well, Liam! Apr 25, Hi mackenzie. We hope the excerpt from this Wonder will help: "An object will float if the gravitational downward force is less than the buoyancy upward force. Eli Mar 15, The average density of the ship includes both the weight of the vessel and the empty spaces of air on board. This must be less than the average density of the water, which thankfully in the open ocean is very dense.

So dense is the body of water in fact that a giant cruise ship is light as a feather on its vast surface. There must be ample air to keep the vessel afloat. An analogy to demonstrate this is to think about a bowling ball being dropped into the ocean as compared to a beach ball.