Question

Is there a case where `N`, normal force = `f`, frictional force?? When a nail is hit into an object?

Answer 1

The equation relating the friction force and the coefficient of kinetic friction is

`ulbar(|stackrel(" ")(" "f_k = mu_kn" ")|)`

where

• `f_k` is the magnitude of the kinetic friction force, the force that acts when the object is in motion, and in the direction opposite to the motion

• `mu_k` is the coefficient of kinetic friction

• `n` is the magnitude of the normal force exerted by the surface the object is on

From a mathematical approach, if the friction force `f_k` equals the normal force `n`, then

`f_k = (1)n`

The coefficient of kinetic friction is then equal to `1`.

So we're basically asking for situations where the coefficient of kinetic friction of the two interacting materials is equal to `1`.

According to this web site, there a few materials where the static friction coefficient is equal to `1`, but no values of `1` are listed for the kinetic friction coefficient. That doesn't mean it's not possible, it simply means it hasn't been documented on that site.

Maybe you could find one yourself!