What is Friction?
Part of the Mechanics section of Coddy's Physics journey. Lesson 15 of 97.
Friction is the force a surface puts on an object that slides, or tries to slide, across it. It acts along the surface, against the sliding.
Friction acts along the floor, against the sliding. N is perpendicular to the floor.
Friction grows with the normal force :
has no unit and depends on the two materials.
Challenge
A box slides to the right across a floor, and nothing pushes it. The friction coefficient is . Find how fast the box slows down: its acceleration .
Try it yourself
Solve for
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Mechanics
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Right TrianglesWhat is a Vector?Adding VectorsAxes and DirectionsVector ComponentsForces Around UsFriction and TensionNewton's First LawNewton's Second LawNewton's Third LawRecap - Net Force