Are sinking objects buoyant? Is the object that sinks to the bottom really also subject to buoyancy

Regarding buoyancy, we should start with the cause of buoyancy, the cause of buoyancy is the pressure difference between the upper and lower surfaces of the object by a liquid or gas, if there is a pressure difference, there must be buoyancy. The absence of pressure difference is generally when the object is tightly bound to the lower surface of the container, and there is no buoyancy at this time.

Yes, the buoyancy does not change when sinking, and it sinks due to the downward force of the combined external force.

As long as the object is in the water, it is subject to buoyancy.

When the density of the object is greater than 10 to the third power, the object sinks until the lower part of the liquid, still keeping the buoyancy less than the gravitational force.

When the density of the object is greater than 10 to the third power, the object floats upwards until the object floats, and the buoyancy of the object is equal to the gravitational force of the object.

When the density of the object is equal to the cubic of 10, the object is suspended.

Yes, as long as there is a discharged liquid, there will be buoyancy.

Sinking only because gravity is greater than buoyancy.

Of course there is, because as long as an object is in contact with a liquid or gas and part of it is in the liquid or gas, it is subject to buoyancy, but when the object sinks, we don't seem to be subjected to upward force, but its buoyancy is still equal to the volume of water it displaces, and the reason why it sinks is because it is buoyant is less than its own gravity, and you can see why it is downward by drawing a force analysis diagram.

Absolutely. To see whether an object retracts buoyancy or not, it depends on whether the object dislodges the volume of liquid.

Yes. When the object is completely submerged, the object sinks and the buoyancy does not change.

Yes, you can use force analysis to help you understand.

1. The object that sinks to the bottom is also subject to buoyancy, and the reason for sinking to the bottom is because the buoyancy of the object is less than its own gravity. However, it should be noted that if the bottom of the object is in close contact with the container, i.e. the bottom of the object is completely free of water (such as a bridge pier or a wooden stake driven into the bottom of a river), it is not affected by buoyancy.

2. The object immersed in the fluid will be subjected to the force of the fluid held up vertically, which is called buoyancy. Buoyancy refers to the difference (resultant) of the fluid pressure on each surface of an object in a fluid (liquid and gas).

Generally, objects do not fit the bottom surface when they sink to the bottom, such as sinking stones, which are still buoyant after sinking to the bottom, and they do not float up because the buoyancy is less than their gravity. If a very small number of objects sink to the bottom and fit the bottom surface, they are not subject to buoyancy. If the ship sinks to the bottom of the beach, Duan Shouxiang's bottom is in close contact with the sand on the bottom, and there is no buoyancy.

1. Refutation of rumors about whether there is buoyancy in the grip object sunk under the water:

The above statement is not entirely correct, and it requires two conditions for it to be true: (1) the side surface of the object must be upright or inclined inward, not outward; (2) The lower surface of the object must be technically in close contact with the bottom of the container, and no liquid can penetrate into it.

In other words, what we call sinking here is not the appearance of sinking, but there must be no gap between the two, and no air can pass through. After the above conditions are met, let's analyze how many forces the object is affected by.

2. Force analysis of objects sunk under water:

In essence, the object sinking to the bottom of the water is affected by three kinds of forces: the object is stopped by the action of the vertical downward gravity g, the vertical upward support force f support and the vertical upward buoyancy f floating, and is in a state of equilibrium, from the center of gravity of the object, along the line of action of the force, make a schematic diagram of the force on the object.

At this time, the force situation: F float + F branch = g object Of course, if the object is in contact with the container at the bottom of the water and there is no air (vacuum), then the object is not affected by the buoyancy of the water.

3. Whether the object sinks to the bottom of the water has buoyancy:

First of all, we should understand that there is not necessarily buoyancy when an object sinks to the bottom of the water.

1. The regular-shaped cylindrical seepage object, after sinking to the bottom, is sealed with the bottom surface and is not subject to buoyancy. Note: The sealing here means that the bottom of the water is very flat, the object is also very flat, and the two fit together.

For example, if the piers are buried in the riverbed and are not subjected to the upward pressure of the water, the piers are not subject to buoyancy.

2. Generally, the object sinks to the bottom and is not sealed with the bottom surface, that is, the pressure of the water on the lower part of the object is greater than the pressure on the upper surface. Objects are subject to buoyancy, and they do not float because they are less buoyant than their gravitational force;

Therefore, it is not that an object is not subject to buoyancy, but that it is subjected to a greater gravitational force than buoyancy.

F float = pvg

p (pronounced "meat" here) is the density of the liquid to be discharged.

v is the volume of the liquid that is discharged.

g is generally sometimes required to take 10) in the question

1 When the object sinks to the bottom, g matter = f float + the bottom floats or levitates on its supporting force, g matter = f float.

You said that "there is no buoyancy when the object is tightly bound to the bottom of the container" - this starts from the cause of buoyancy, the reason for the buoyancy is that "the pressure difference between the upper and lower surfaces of the liquid on the object immersed in the liquid" is deeper than the shallow, so the resultant force is an upward buoyancy (vertical upward), which is buoyancy.

If the object is tightly bonded to the bottom of the container, the lower surface of the object cannot experience the force because there is no liquid.

Understand? If you don't understand, just ask.

Q: 819350652 (I am going to take the high school entrance examination recently, and I don't have much time to go to it, after June 14th).

Very simple.

In fact, buoyancy is the volume of water discharged by the two, and the buoyancy force is the gravitational force of the water discharged, no matter how dense it is.

However, if the ball is water, it will sink to the bottom.

And buoyancy = g row.

Ball = Water. Levitation, buoyancy = g row = g ball.

Seek < water.

then floats, buoyancy = g row = g ball.

If you want to calculate buoyancy, you only need to calculate the gravitational force of the liquid when the object sinks.

Because according to Archimedes' principle, the gravitational force of the object discharging the liquid, that is, the buoyancy experienced by the object, then it does not matter whether the object sinks, floats or floats in the liquid. Just calculate the gravitational force of the object discharging the liquid, and the gravitational force of discharging the object from the liquid. It can be calculated based on the volume of the object and the density of the liquid in the city due to the acceleration of gravity.

If you calculate the sinking buoyancy of an object after high school, then you can calculate the buoyancy according to the equilibrium state of the two or the accelerated motion state of the object, and according to the knowledge of dynamics. Then this method of calculating buoyancy is also available.

In the process of sinking, the buoyancy of the diver is equal to the gravitational force of the water he dissipates.

(1) If the object is completely immersed in the soft mud at the bottom of the water, the buoyancy will be zero.

2) If part of the volume of the object sunk to the bottom (V row) is exposed above the soft mud and comes into contact with the water, buoyancy f = water. Row.

3) If the bottom of the water is flat and free of mud and grass, the volume of the object sinking to the bottom is v, and the buoyancy f = water.

Sinking object buoyancy = gravity in air - gravity in water.

As long as an object is immersed in a liquid, it will be subject to the upward buoyancy of the liquid, and the greater the gravitational force of the liquid, the greater the buoyancy will be exerted.

When an object sinks to the bottom, it can only mean that the gravitational force on the object is greater than the buoyancy force on it.

When the gravitational force exerted on the object is less than the buoyant force exerted on it, the object floats upwards and finally floats on the surface of the liquid.

When the gravitational force exerted on the object is equal to the buoyant force exerted, the object is suspended and can stop anywhere in the liquid.

If there is no liquid under the object, then the object is not subject to buoyancy, because buoyancy is "there is a pressure difference between the upper and lower surfaces", that is, the upward pressure is greater than the downward pressure, and this difference is buoyancy, and now there is no upward pressure, of course, there is no buoyancy.