What is static friction? what are the advantages and disadvantages of static friction? thanks!?

Question

You can also give me sites where i can find more answers... thanks!

Answer 1

Static friction is the force between 2 bodies that are NOT moving.

Say that you're pushing a box which is on the ground. There is a minimum amount of force that you have to apply to get the box moving.

This force is equal to the static friction force (F) between the 2 bodies where (F) is calculated from:

F = μR

Where: μ = coefficent of friciton

           R = Reaction of ground on box which is = to wieght of box

Note: This formula gives you the value of limiting friction ( the maximum value of static friction )

An advantage includes preventing a car wheel from slipping or a shelf hanging on a wall.

Static friction can alse be a nuisance when it comes to hindering movement in say any mechanical device/machine etc...

More on friction can be found here if you want to:

http://en.wikipedia.org/wiki/Static_fric...

Friction explained from a mathematical view:

http://cnx.org/content/m14068/latest/

Answer 2

Static friction is the resisting action between any two materials in contact.

It depends the surface finish ( smoothness ) of the two bodies and on the weight/force that causes the contact.

a basic formula : F = u * N

F : friction force

u : coeffecient of friction

N : the weight/force causing the contact