Question

Define the term 'coefficient of limiting friction between two surfaces. A body
of mass 10 kg is placed on aninclined surface of angle 30°. If the coefficient of
limiting friction is to find the force required to just push thebody up the
inclined surface. The force is being applied parallel to the inclined surface.​

Answer 1

Coefficient of static friction is applied t bodies which have not moved yet due to a force but can move if a slight additional force is applied to them.

Given:

Mass of the body = 10 kg

Angle of inclination = 30°

Coefficient of limiting friction = µ

To find:

The force to be applied to just push the body up the inclined surface.

Solution:

The force that is making the body to slide down the incline = µmg sin 30° = 49µ N

To balance this force one would need a force of 49 N but in the opposite direction that is upwards along the inclined surface.

Therefore, we would need only a slight force greater than 49µ N to push the body up the inclined surface.