What happens if throw a sealed soda can into the deep ocean? Will it implode or just reach a equilibrium level? Has anyone ever tried this, and attached a piece of fishing line so you can see what happens?
The can will float in salt water. Usually. Some non-carbonated beverages might sink. I dropped a can of coke in the ocean once, and it floated. If you could get a can to sink, I’d guess that it would eventually sink far enough where the pressure would crush it.
No, the can would not be crushed. Assuming it would sink in the first place, it would reach an equilibrium point and go no further unless acted upon by an outside force.
for an example of this: get a glass, fill it half with water, half with cooking oil. drop and icecube into the glass, and the it will sink through the oil to the point of water surface.
Hmmm. I would think that it a static object (i.e., not a submarine) is either going to float, or sink to the bottom (unless its specific gravity is exactly 1). Water is not compressible so its density does not change through depth changes.
I would think that a sinkable can that has some air (or other gas) would sink until the pressure outside was greater than the pressure inside, causing the can to crush. Assuming the surface of the can did not breach in the crush, the can is now denser, and would continue to sink, and continue to be crushed, maintaining this pressure equilibrium until it hit the bottom. Along the way, the free gas may be forced into solution in the liquid, I’m no chemist so I’m not sure about that. I also don’t know if there is air in the can, or just CO2.
If the surface is breached, the gas and possibly the liquid likely all escapes and the game is over, now you just have a sinking hunk of metal.
I don’t see the analogy, since seawater doesn’t have density layering.
Not sure I see the reasoning here. How would you define the equilibrium point? This would be true of an object (e.g., balloon) floating in the air, but the density of air becomes lower with altitude. Water doesn’t change density, just pressure.
Seawater does have a density gradiant though, I think this is what Destination Unknown is trying to illustrate.
Actually, fluids do change density with pressure. The effect is usually small and can be ignored for most calculations, but it does exist and cannot be ignored for the depths and pressures encountered in the ocean.
Thus:
I agree, assuming it would sink (would it sink in fresh water?), it would reach equilibrium and go no further.
Soft drinks sink in fresh water. Methinks QED had a diet soft drink go overboard. Beer and diet drinks float in fresh water and regularly sweetened cans of soda sink.
I’m going down to the beach here shortly to look at the storm surf and I’ll take a regular Coke with me to try the saltwater buoyancy question.
Film at 11…
Maybe attach a rock to it & see what happens then?
I recently went to a lecture at the Monterey bay Aquarium & the lecture person brought a tiny styrofoam cup to show us & said it had been taken deep down in the sea in a ROV. It became pretty small but retained its shape perfectly.
Yes, fluids do change density with pressure to some extent. I think, though, that the fluid in the can would also change density with pressure so if the can’s density is greater at the surface it would remain greater unless it hit an ocean layer of higher salt concentration.
Just to round this up, this site gives the bulk modulus of water as 2.2*10[sup]9[/sup] N/m[sup]2[/sup]. At the bottom of the Mariannas Trench water is a little over 4% denser than it is at the surface, and so is the water in the can. Assuming the can sank at all.
When you have a cooler full of ice, drinks and beer…and the ice melts so that only water is left, the drinks and beer are not floating. They are definately laying on the bottom of the cooler.
right, but remember that’s fresh water, which is less dense than salt water. Many things which can sink in fresh water (like an egg) will float in salt water. Try it at home.
Remember that the can has basically just water inside. It’s only going to crush as much as the air-space allows, plus a little bit more as the water compresses a bit. Since the cans themselves are pretty easy to squeeze, and since aluminum is denser than water, the can’s overall density will be greater than water at some distance down, and the can will just keep falling after that. But it won’t crush that much since it’s mostly full of water.
It’s possible that the salt water is enough denser than the beverage to more than account for the aluminum, but I’d have to see some figures to believe this.
The density of sea water does vary, but not as a function of pressure, the variation is caused by differences in salinity and temperature. At a sufficiently high pressure all gas inside the can (primarily carbon dioxide) will be forced into solution and there will be no void space. At this point the can would sink or float depending on the weight of the can, the density of the contents and the density of the surrounding water. Deep ocean waters tend to be very salty and cold and thus quite dense, so it may be possible for an incompressible object that just sinks at the surface to become neutrally buoyant at some depth. The water inside the can will compress very slightly but this has no net efect since the sea water is also subject to the same pressure and thus the same rate of compression.