To transport a series of bundles of shingles A to a roof, a contractor uses a motor-driven lift consisting of a horizontal platform BC which rides on rails attached to the sides of a ladder. The lift starts from rest and initially moves with a constant acceleration a(1) as shown. Knowing that the coefficient of static friction between a bundle of shingles and the horizontal platform is 0.25 , determine the largest allowable acceleration a(1) , if the bundle i, NOT to slide on the platform. (Fig 2).

To transport a series of bundles of shingles A to a roof, a contractor uses a motor-driven lift consisting of a horizontal platform BC which rides on rails attached to the sides of a ladder. The lift starts from rest and initially moves with a constant acceleration a(1) as shown. Knowing that the coefficient of static friction between a bundle of shingles and the horizontal platform is 0.25 , determine the largest allowable acceleration a(1) , if the bundle i, NOT to slide on the platform. (Fig 2).

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 7.3P: Two identical chairs, each weighing 14 lb, are stacked as shown. The center of gravity of each chair...

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