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Anonymous users2024-02-11The kinetic friction factor is only related to the materials of the objects in contact with each other, and is related to the smoothness of the surfaces of the objects in contact. When two objects are determined, the kinetic friction factor is independent of both positive and sliding friction.
The relationship between the dynamic friction factor and the surface of two objects is not that the smoother the surface, the smaller the kinetic friction factor. In fact, when the surface of two objects is very rough, the dynamic friction factor will be very large due to the staggered coupling of peaks and valleys on the contact surface; For very smooth surfaces, especially very clean surfaces, the kinetic friction factor is greater because the molecular force plays a major role, and the smoother the surface, the greater the kinetic friction factor. But in mechanics, it is often called"The surface of the object is smooth"This is a reference to ignoring the friction between objects, and is in fact an idealized model that has nothing to do with the above description.
For metals, their dynamic friction factor in the atmosphere is generally less than 1, and if you try to remove the oxide layer on the metal surface, its dynamic friction factor will become very large, which is the result of the gravitational action between the atoms on the contact surface.
The kinetic friction factor (m) is a unitless physical quantity, which can directly affect the motion state and force of an object.
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Anonymous users2024-02-10The dynamic friction factor is related to the material and roughness of the contact surface.
The magnitude of kinetic friction and sliding friction are related to the pressure of the object on the contact surface.
f=μ×fn
is the dynamic friction factor, and fn is the pressure on the contact surface.
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Anonymous users2024-02-09The dynamic friction factor is related to the material of the contact surface of the two contact objects, and the rougher the material, the greater the dynamic friction factor.
The magnitude of the dynamic friction is related to the positive pressure, and the greater the positive pressure, the greater the dynamic friction.
The magnitude of sliding friction seems to be the same as kinetic friction.
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Anonymous users2024-02-08Normally, you also thought life was very simple when you were a child.
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Anonymous users2024-02-07According to the conditions given in the question, it can be seen that there is an inflow of air bubbles at the A hole. Because, the pressure at hole A is less than the pressure at hole hole.
There is water flowing out of the c-hole. This is because the pressure at hole C is stronger than the pressure at hole b.
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Anonymous users2024-02-06From q=sv, we can see that v does not change. Bernoulli's equation can be used, p+ gh = constant. So the high pressure at A is smaller. There are air bubbles entering. The low pressure is greater at C. There is water flowing out.
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Anonymous users2024-02-05First short: 28 N (upper pressure is equal to lower pressure).
The second space: 10 N (f buoyancy refers to the density of the manuscript body x small gx the volume of the boiled water 1x10 to the 3rd power kg cubic meter x 10 N kg Niu).
Cell phone. Fu Kongyu can't be typed. I apologize for the inconvenience of filial piety. ）
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Anonymous users2024-02-04In the upward pressure book-downward pressure = floating wisdom = 1000*10*
2.The buoyancy of this object is = 1000*10*
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