What is the formula for calculating the force of friction on an inclined plane?

The correct approach for calculating the force of friction on an inclined plane employs the relationship between the coefficient of friction and the normal force acting on the object. The formula for the force of friction is derived from the concept that frictional force resists the sliding motion of an object and is proportional to the normal force exerted on it.

On an inclined plane, the normal force is not equal to the weight of the object (which is m × g) but is instead influenced by the incline angle. The force of friction can be expressed as the product of the coefficient of friction (μ) and the normal force (Force(normal)). In this case, the normal force can be calculated as mg multiplied by the cosine of the angle of incline, but the key point is that the frictional force depends on the normal force and the coefficient of friction that characterizes the interaction between the surface of the incline and the object.

Hence, the formula Force(friction) = μ × Force(normal) accurately captures this relationship, clearly indicating the dependence of frictional force on both the surface properties (described by μ) and the supporting force acting perpendicular to the inclined surface (Force(normal)).