The amount of friction depends on the fluid viscosity and the velocity gradient (that is, the relative velocity between fluid layers). The velocity gradients are set up by the no-slip condition at the ...

As the disk continues to roll with slipping, the friction force also produces a clockwise rotation of the disk. Once disk picks up enough angular velocity to produce a no-slip condition at the contact ...

Another of Amontons’ laws states that sliding friction force is independent of sliding velocity. People have known for many ...

and there is no friction. Although these restrictions sound severe, the Bernoulli equation is very useful, partly because it is very simple to use and partly because it can give great insight into the ...

For example, measurements of the force required to drag the aluminium tip of a scanning tunnelling microscope over a gold surface estimate a friction force, linear in velocity, of the order of 10 ...