Which of the following best describes how the magnitude of the frictional force…
PHYSICS · Single correct · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
Which of the following best describes how the magnitude of the frictional force between two dry, solid surfaces depends on whether the surfaces are sliding relative to each other?
(a) Kinetic friction is larger than the maximum static friction because the motion adds an extra resisting force.
(b) While the surfaces are at rest relative to each other, the frictional force adjusts up to a maximum value; once sliding begins, the force takes on a smaller constant value proportional to the normal force.
(c) The frictional force is proportional to the normal force in both cases, and the proportionality constant is the same whether the surfaces slide or remain at rest.
(d) The frictional force does not depend on the normal force and is determined primarily by the surface area in contact.