It isn't always - for instance: static friction (standing still) is greater than moving friction.
BUT, Air resistance (or water resistance for boats) increases with speed - quite rapidly. The reason for the increase is that you must move the fluid out of the way in less time as you speed up.
As speed increases, the magnitude of fluid friction also increases. This is because at higher speeds, there is more interaction between the moving object and the fluid, resulting in greater resistance and friction.
Friction increases as speed increases because at higher speeds, there are more collisions between the moving surfaces, leading to greater resistance. This results in more heat being generated, which in turn increases friction. Additionally, higher speeds can cause deformation of the surfaces, creating more contact points and thus increasing friction.
Actually, friction does depend on velocity. If you stop your car you have to ease up on the brakes as you slow down because friction increases as you slow down. This effect has been observed for objects travelling at bullet velocities. Friction decrease as speed increases.
Static friction is greater than sliding friction. Static friction occurs when an object is at rest and an external force is being applied to move it, requiring a greater force to overcome the initial resistance compared to when the object is already in motion and experiencing sliding friction.
Yes, it is generally true that kinetic friction is always greater than the maximum value of static friction.
it speeds up and speeds down
As speed increases, the magnitude of fluid friction also increases. This is because at higher speeds, there is more interaction between the moving object and the fluid, resulting in greater resistance and friction.
Friction increases as speed increases because at higher speeds, there are more collisions between the moving surfaces, leading to greater resistance. This results in more heat being generated, which in turn increases friction. Additionally, higher speeds can cause deformation of the surfaces, creating more contact points and thus increasing friction.
That depends on the exact circumstances. Solid friction hardly depends on the speed at all. In fluid friction, the situation is more complicated. Usually there is some range of speeds for which friction is more or less proportional to speed; at higher speeds, the force of friction may even become proportional to the square of the speed.
Static friction
Actually, friction does depend on velocity. If you stop your car you have to ease up on the brakes as you slow down because friction increases as you slow down. This effect has been observed for objects travelling at bullet velocities. Friction decrease as speed increases.
Static friction is greater than sliding friction. Static friction occurs when an object is at rest and an external force is being applied to move it, requiring a greater force to overcome the initial resistance compared to when the object is already in motion and experiencing sliding friction.
kinetic friction
sliding friction
Fluid friction is greater.By: Adarsh kv1
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Yes, it is generally true that kinetic friction is always greater than the maximum value of static friction.