1. A 4 kg box is dragged across a horizontal rough surface by pulling on a cord at 0 = 20° above the surface. (a) What minimum force magnitude is required from the pulling cord to make the box move, if the coefficient of static friction is µs = 0.80? (b) Maintaining the magnitude of the force as in part (a), what is the magnitude of the initial acceleration of the box, if the coefficient of kinetic friction is µx = 0.65?

1. A 4 kg box is dragged across a horizontal rough surface by pulling on a cord at 0 = 20° above the surface. (a) What minimum force magnitude is required from the pulling cord to make the box move, if the coefficient of static friction is µs = 0.80? (b) Maintaining the magnitude of the force as in part (a), what is the magnitude of the initial acceleration of the box, if the coefficient of kinetic friction is µx = 0.65?

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter5: More Applications Of Newton’s Laws

Section5.1: Forces Of Friction

Problem 5.3QQ: You are playing with your daughter in the snow. She sits on a sled and asks you to slide her across...

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