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Forces
A force is an interaction that would change the motion of a given object.
Mass is the density of the object while weight is its resistance against gravity. Volume is related to mass via density.
Weight
Weight is mass multiplied by gravity. $w = mg$
Friction
Friction is a force caused by the collision of surfaces that are inherently uneven. It is mathematically defined as $F_r = \mu F_n$ where $F_r$ is friction, $F_n$ is the normal force1), and $\mu$ being the coefficient of friction2).
1)
opposing force of weight when object is resting on a surface
2)
Newton's second law is useful here if you want to find the friction coefficient given an acceleration without mass present
