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Why is the buoyancy equal to gravity when an object floats or floats? The volume of water overflowing during floating is different from that during suspension. Why is the buoyancy the same?
Because they are static at that time, it means that the force is balanced, but only affected by two vertical forces
Buoyancy can not be the same, an object can not be floating and suspended in the same liquid
Is the buoyancy of an object suspended or floating in a liquid equal to its own gravity?
Well
A suspended or floating object is only subject to gravity and buoyancy in liquid, and is still. These two forces are a pair of equilibrium forces, so buoyancy is equal to gravity
Why is buoyancy equal to gravity when floating
Floating on the water, we understand that the object is static in the vertical direction,
According to Newton's first law, the external force on a stationary body is 0,
However, the vertical direction is only affected by gravity and buoyancy, so it must be in the opposite direction
Archimedes' principle is that buoyancy is equal to the volume of liquid. When an object floats or floats, buoyancy is equal to gravity. Is that self contradictory
Buoyancy is equal to the gravity that displaces the liquid. When an object floats or floats, buoyancy is equal to gravity, and the object is just in balance
When buoyancy floats in water, buoyancy = gravity. When is buoyancy equal to gravity in air
For example, if a balloon hovers in the air or rises or falls at a constant speed, then buoyancy equals gravity
To solve this problem, we can balance the knowledge of two forces and analyze the state of physical motion
If a body is at rest or moving in a straight line at a constant speed, then the body is in a state of equilibrium, then it is subject to a balancing force, and the two forces are equal
Hope it works for you
The following statement about Archimedes principle is wrong: the buoyancy of an object immersed in liquid is the gravity of the liquid displaced by the object
The buoyancy of an object immersed in a liquid is the gravity of the liquid it displaces?
Wrong. Two forces are equal in size, not the same force
Buoyancy is the force of a liquid on an object in an upward direction
Gravity is the earth's resistance to liquid, downward
They are not the same force
It can be changed that the buoyancy of an object immersed in liquid is equal to the gravity of the liquid displaced by the object
Archimedes principle tells us: the buoyancy of an object immersed in water is equal to the gravity of the object to drain water
Archimedes principle tells us: the buoyancy of an object immersed in water is equal to the gravity of the object draining water. What is the buoyancy of 20n water
A. Always less than 20n B. always equal to 20n C. always greater than 20n D. can be greater than 20n
D
Why?
First of all, let's make it clear that f floating = g row (and g row is not necessarily equal to G overflow). The so-called drained water can actually be understood as the volume of 20n water in the "non water part" under the water surface. After calculation, the volume of water is 2dm3. We can imagine that the volume of an object is 3DM3, so let the water cover the object thinly, then
When an object floats or levitates, buoyancy is equal to gravity, and buoyancy is equal to the gravity that displaces the liquid. Therefore, the gravity of displace the liquid when floating or levitating should be equal. Obviously, the gravity of displace the liquid when floating and levitating is different,
The same object can't float and float at the same time, so there's no problem for you. Of course, different objects can float or float to drain water with different gravity
Why is buoyancy equal to gravity?
Isn't buoyancy equal to the gravity of the drained water?
So if an object floats on the surface of the water, part of it is exposed. The volume of the discharged water is not equal to the volume of the object. Although the density is different, the gravity is not necessarily the same!
Buoyancy equals gravity, which is wrong
When an object sinks to the bottom, buoyancy is less than gravity
When an object floats or floats, it has buoyancy = gravity
At this time, the object is in a state of equilibrium (static) and is subject to equilibrium force. In the vertical direction, it is only subject to gravity and buoyancy, so buoyancy = gravity
If buoyancy is less than gravity, the resultant force of buoyancy and gravity will make it decrease
If buoyancy is greater than gravity, the combined force of buoyancy and gravity will make it rise
So it can only be buoyancy = gravity
How to judge whether P = pGH or gravity
First of all, buoyancy is always equal to the weight of the liquid, but in some cases, you can't know how much liquid is drained. In the case of floating, part of the object doesn't sink into the liquid, and doesn't drain the liquid. In this case, you can't know how much liquid is drained
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