Two bicycle tires are set rolling with the same initial speed of 3.3 m/sm/s along a long, straight road, and the distance each travels before its speed is reduced by half is measured. One tire is inflated to a pressure of 40 psipsi and goes a distance of 19.0 mm ; the other is at 105 psipsi and goes a distance of 93.8 mm . Assume that the net horizontal force is due to rolling friction only and take the free-fall acceleration to be g� = 9.8 m/s2m/s2 . What is the coefficient of rolling friction μr�r for the tire under low pressure?

Two bicycle tires are set rolling with the same initial speed of 3.3 m/sm/s along a long, straight road, and the distance each travels before its speed is reduced by half is measured. One tire is inflated to a pressure of 40 psipsi and goes a distance of 19.0 mm ; the other is at 105 psipsi and goes a distance of 93.8 mm . Assume that the net horizontal force is due to rolling friction only and take the free-fall acceleration to be g� = 9.8 m/s2m/s2 . What is the coefficient of rolling friction μr�r for the tire under low pressure?

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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