friction (1 Viewer)

[untouchablecuz]

why is friction directly proportional to the normal force? whos to say there isn't an exponential, sinusoidal etc relationship?

 

[madsam]

Physical testing

And i'm sure there's some theory there too

 

[untouchablecuz]

Physical testing

And i'm sure there's some theory there too

but how can physical testing generalise that F_f = kN in all instances, on all surfaces

 

[Sokolov]

friction force is taken at an instantaneous point in time.
most physical problems involve something in contact with a surface at a steady state and its often the weight that acts opposite to the normal force.
provided it doesnt slip.

 

[madsam]

but how can physical testing generalise that F_f = kN in all instances, on all surfaces

empirical formula's brah, with enough data a relatively close approximation can be made

If you did quanta to quarks, Rydberg's equation and constant, for example