Questions tagged [buoyancy]
Use "buoyancy" for any question where an object is suspended or submerged in a fluid. Buoyant force is the force that acts upward on a partially or completely submerged object.
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What is the Buoyant force experienced by a cube at a certain level inside water?
I'm not able to comprehend the meaning of buoyant force. As per Archimedes Principle, it's the force equal to the weight of the volume of water displaced by the body. But wouldn't this be only true ...
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Does buoyancy force depend on the acceleration of the buoyant object?
According to Archimedes' principle, the buoyancy force on a submerged object is given by the product of the mass of the displace fluid and the gravitational acceleration. Effectively, it is determined ...
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How does a static fluid exert pressure in upward direction? [duplicate]
I was going through the derivation of a mathematical equation for the upthrust exerted on a body which is given in my book.
It says that the downward pressure exerted on the upper surface is less than ...
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Why are there 2 ways of predicting if an object will float or not?
I thought about it for a second, I have always thought that for an object to float it had to be less dense than water, and if it had more density then it would sink. But then if it sinks or floats ...
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According to an equation I derived, an object with negligible height would always sink. Where is it flawed?
Assume that an object has negligible height, i.e., height is approximately $0m$.
If we immerse this object in water, will it float or sink? In order to find this out, we need to calculate the net ...
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Buoyancy with Object of Heterogeneous Density [closed]
The Archimedes buoyancy principle usually seems to be taken for objects of homogeneous density. So for example a sphere would have mass equal to $(4/3) \pi r^3 \rho$, where $\rho$ is the density. ...
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How does the hydrostatic paradox operate when a column of lighter liquid rests atop a “floor” of heavier liquid?
I know that, according to the hydrostatic paradox, the height of a homogeneous liquid is the only determinant of pressure within that homogeneous liquid, and the shape of its container does not affect ...
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Is the buoyant force on an object a kind of normal force?
So, simple question, are the bouyant force applied to an object by a fluid and normal force (Is it even there?) related?
If no where is the normal force and why does bouyancy even happen?
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Is there a depth under which the buoyant force is no longer sufficient to bring a diver back to the surface? [duplicate]
I came across the story of diver Yuri Lipski who died while diving in the Blue Hole.
This made me wonder something and it may be a stupid question but I thought I'd ask:
For a human diver with normal ...
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Sealed container with half-open gas buoy
Consider a sufficiently rigid and sealed container completely filled with liquid (e.g. water), pressurized at 1 bar, at constant temperature. Inside the container there is a buoy partially filled with ...
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Is it correct to say that "WE" feel only 5/140 of the actual weight of brain as buoyancy acts on brain due to cerebrospinal fluid?
Many sources of biological sciences (e.g.https://medium.com/@drvnx/what-is-that-thing-without-which-we-are-dead-f556fb1029ef ) say that the actual weight of brain is almost 1400gwt but as brain ...
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Will the water level change due to releasing a ironic ball from a floating ice cube? [duplicate]
A piece of ice is floating in a glass of water. There is a small ironic ball inside the piece of ice.
If the ice completely melts, the ball will be released into the water. Then will there be any ...
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How to derive the formula of the buoyant force?
I've seen some variations of this question on the forum, but none has satisfactorily cleared up my confusion, so I made this post with information about what I take issue with specifically. Thank you!
...
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Buoyancy force vs object weight
If an object is floating (partially or fully), does the buoyancy force = the weight of the entire object?
My confusion is,
situation A: 100g object is 50% submerged and floating
situation B: 100g ...
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How does inertia affect an object suspended in a fluid?
When I asked my physics teacher how fully submerged objects are suspended in fluids, she told me it was because the object's density was equal to that of the fluid's as a result of the net force ...
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Feeling of coldness in heights
We know that due to buoyancy the cold air sinks and warm air floats above it due to it being less dense than cold air. Then why do we feel cold as we go to greater heights/hill stations and feel hot ...
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Why do some objects tend to sink after some time in water even if they float at the start?
I have observed this phenomenon in swimming pools: I have seen many dead insects floating on the surface, but after some time some they tend to sink down without any external influence. Why does this ...
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About the floatation of bodies on a surface
A body which is partially floating in water is in equilibrium due to the balancing of the buoyant force and the weight of the body. Now what will happen to a body floating on the surface of the liquid ...
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Buoyancy, mechanic of fluids hydrostatics
I am struggling to understand how to solve buoyancy problems, and I have one that would help clarify my mind if you could help me, please. There is a tank with depth H and a plug at the bottom of the ...
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How does buoyant force formula work if it got nothing to doi with the dencity of the object?
Google tell me the formula for buoyant force is Fb = -pgV Where Fb is buoyant force and p is fuid dencity , g is gravity index, V is fuid volume which I suppose is just like the volume of the object. ...
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If fluids exert force in all directions then why do objects float? [duplicate]
My question is that when we place a body in water it exerts a buoyant force but it exerts an equal force in downward direction then why its buoyant force is greater and the object floats?
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Why doesn't this buoyant free energy device work?
Okay so I've seen a few of these but the setup here is a bit different.
Suppose we set up an electrolysis plant at the bottom of the ocean and for some constant energy cost $E_1$, we can get a bunch ...
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Confusion regarding direction of buoyant force
In this question, we are given the density of oil, water and the block. We are given that the block is floating, and thus we need to find what fraction of the block's volume lies in the oil. I have a ...
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Does an object submerged in water affect the total weight of the water tub, if the displaced water is spilled out?
Suppose you have a tub filled to the brim with water and it rests on a scale so you can measure the weight. Any displaced water is spilled out of the tub and so no longer contributes to the weight ...
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Why wouldn't this perpetual motion machine based on Archimede's principle work? [duplicate]
I found this today on the interwebs:
Obviously this cannot work, but what bugs me is that I cannot figure out the part that would stop it and bring it to equilibrium. I suspect that it has to do ...
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Why is an object considered less buoyant if it is fully submerged? [closed]
I found the following on BYJUS:
A body experiences greater buoyant force when it is fully submerged compared to when it is partially.
https://byjus.com/question-answer/a-body-experiences-greater-...
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Buoyancy force | What is the correct way to describe and explain Buoyancy force at a macroscopic but also a microscopic perspective
Have you ever noticed objects going down in a pool, reaching equilibrium? Often, when a submerged object (and in contact to the floor) is moved, it start going up again. Why?
This kind of scenarios ...
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Deriving Formula for Archimedes' Principle [duplicate]
Let B be the buoyant force acting on an object and W be the weight of the fluid it displaces.
I can't derive the formula for Archimedes' Principle: B = -W
I have found plenty of derivations for B = W ...
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Buoyancy forces on a tube exposes to Atmosphere at both ends that passes through a container filled with liquid
I'm trying to get an understanding of a free body diagram for the following situation. A container, such as Styrofoam cup has a straw pushed through the bottom of it and the cup is filled with water. ...
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How to calculate forces on a water absorbant object submerged in water?
I already found this thread but it didn't help me. I have a block of rubbery material that is much heavier than water and can shrink a little under pressure. It is also water absorbent.
If I submerge ...
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Is anti-matter less dense than a vacuum?
Fill a balloon with Helium and it floats (it is buoyant in air). 'Fill' a balloon with a vacuum (not withstanding the difficulty of a structurally stable void) and it is more buoyant as it is less ...
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Buoyant force in a tub filled with multicolour balls
Would there be a buoyant force on a moving object like a human in a multicoloured balls(say 1cm diameter) filled tub? Or would it be like a superfluid, so that the human would sink right in without ...
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Could not agree on the correct answer on the following question [closed]
The following question was asked in a national teacher selection examination, and there were opposition based on the fact that the announced key was wrong and it should be changed. The question is ...
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Relativistic Archimedes principle in geometric calculus
A submarine moving with a relativistic velocity v can be modeled by a liquid volume with the same intrinsic density $q$ as the liquid medium.
The apparent paradox is that the sub either sinks or rises ...
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Oil and gravity
If we put oil in a cup and then we put water in the same cup, the oil will rise to the top. But isn't gravity supposed to stop that. Like if the oil was at the bottom isn't it supposed to stay there ...
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Confused about how the formula for buoyancy is derived
The formula for fluid pressure of any point at depth $h$ in a fluid is $p = hρg$. Here, the formula is derived by calculating the mass of the fluid column above the point (which is equal to $Ahρ$, and ...
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Buoyant force on the closed hollow object with trapped air submerged into the water
I need help to understand the buoyant force action on the hollow object with trapped air submerged into the water. Does the BF equal to the volume of the hollow section of the object multiplied by the ...
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Sealed container with water with air bubble at the top — Basic hydrostatic principles fail? What is the pressure distribution?
From hydrostatics, it is said that when you have a liquid with no moving parts, the pressure does not vary on any horizontal slice of the liquid. The pressure only varies with depth.
Thinking about ...
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How the weight of an object lighter than water changes if it is pushed and tied to bottom, going upwards and floating on the surface? [closed]
Imagine I push an object to the bottom of water with a rope (through a ring at the bottom) and attach the rope to the top of container. If I cut the rope the object will go upwards.
will there be ...
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Yet another perpetual motion machine: does this imply large selective membranes are not possible? [closed]
So I was just thinking about the buoyant force and came up with what seemed like a simple perpetual motion based on it. Obviously such things are not physically possible so I'm trying to figure out ...
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Do you weigh more with suction cups under your feet on the scale?
The scale weighs everything on top, including the air. So if you turn on the suction cups, and they suck vacuum (i.e., air is taken out), the scale will give a fraction less weight (I didn't calculate ...
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Time it takes for an object to sink?
I am trying to determine how long it takes for an object to hit the bottom of the water. I've been looking at Stoke's Law, but can't quite figure out how to get to my answer.
Obviously, there are a ...
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Calculating the required volume of Helium to put in a weather balloon [closed]
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I am working on a project where we will launch a weather balloon with some scientific instruments tied beneath the balloon. We fill the balloon with helium from tanks of compressed helium. ...
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Resulting height of displaced fluid after adding a floating object
I've had contradictory experimental results from my calculations of displaced fluid height after adding a floating object.
Consider the following scenario: Using a test tube of diameter $D=1.70$ cm ...
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DISPLACEMENT OF WATER [duplicate]
Floating objects displace their weight?
what does this statement actually mean?
Does this mean that floating objects displace the amount of water that's equal to their weight and so buoyancy is equal ...
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Displacement of water - Archimedes' principle
Floating objects displace their weight and objects that are completely submerged in water displace their volume. So, my question is that does a floating object displace less water than an immersed ...
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What is $V$ in Buoyant force $V\rho g$? [closed]
As, Buoyant force is the net upward force on any object in any fluid. If the buoyant force is greater than the object's weight, the object will rise to the surface and float. If the buoyant force is ...
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Shape of a floating candle floating in an infinitely large cylindrical tub of water that maintains its height
I was asked by a friend to determine the shape of an axially symmetric candle floating in water in a tub in such a manner that the wick maintains its height with respect to the ground. The fall in ...
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Which tube experiences a larger buoyant force?
I saw lots of debate about this question. Some are saying that this cannot be solved because the weight of the tubes is not given. Others say the red one experiences more buoyant force because for red:...
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Buoyancy versus viscosity
A common problem in casting is removing the air bubbles that might might be in the mold material, like plaster or resin. This is typically done by degassing--putting the mold material under vacuum to ...
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