1. A 2.0 kg box is initially at rest on a horizontal surface with friction. At t=0 a horizontal force F=(2.4t)i N (t in seconds) is applied to the box. The acceleration of the box as a function of time t is given by a=0 for Ost<3.0 and a=(1.2t-3.0)i m/s² for t>3.0 s. a) What is the static friction constant between the box and the surface until motion starts? b) What is the kinetic friction constant between the box and the surface after motion starts at t=3s?

1. A 2.0 kg box is initially at rest on a horizontal surface with friction. At t=0 a horizontal force F=(2.4t)i N (t in seconds) is applied to the box. The acceleration of the box as a function of time t is given by a=0 for Ost<3.0 and a=(1.2t-3.0)i m/s² for t>3.0 s. a) What is the static friction constant between the box and the surface until motion starts? b) What is the kinetic friction constant between the box and the surface after motion starts at t=3s?

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter4: The Laws Of Motion

Section: Chapter Questions

Problem 9WUE

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