I don't understand any of the basic principles of buoyancy. Can someone explain them better to me?

Question

This applies to physics, like the formulas, principles (Arcimedes), etc.

Answer 1

Here's what I remember. An object has mass and volume. If you immerse it in a liquid, it will push away some of the liquid. If it goes all the way under, the volume of liquid it pushes away will be equal to the volume of the object.

Now, if that volume of liquid has more mass than the object, then it won't go all the way under. It will only sink until it's displaced a mass of liquid equal to its own mass. That's why things that are less dense than water float.

You can make objects that float out of materials that are heavier than water, like boats, by making them hollow. The volume they displace is the same as if they were solid, but the weight is much less, so they act as if they were much less dense.

You can calculate the density of an irregular object by weighing it, then measuring the volume of water it displaces. That's what Archimedes was so excited about. He was trying to figure out if a crown was pure gold or not, and he knew that at the time, gold was the heaviest known element. He weighed the crown, then filled up a tub all the way to the brim and lowered the crown in. The water spilled into a basin, and he was able to measure it and find the volume of the crown. Then he divided the mass by the volume to get the density, and compared it to the density of gold. History doesn't record whether the crown was real or not.

Answer 2

You are floating on dirt as you walk. Why don't you sink into the ground? Because the area under your feet can support your weight. When you go to the beach you sink in the sand to a point. That point is when the ground is more dense than your weight. Same goes for snow skiing. Skis sink until a balance is reached between the strength of the snow and your weight. This is how a large ship stays afloat. It will sink until the water displaced equals the weight of the ship.

Answer 3

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