A man who weighs 180 lbs.is riding in an elevator. Find the force exerted on the man by the floor of the elevator under the following conditions: (a) The elevator is accelerating upward at 12 ft/sec2. (b) The elevator is accelerating downward at 12 ft/sec2. (c) The elevator is accelerating downward at 32 ft/sec2. Have we made any restrictions on the directions of the velocity in parts (a), (b), and/or (c)? If so, what?

A man who weighs 180 lbs.is riding in an elevator. Find the force exerted on the man by the floor of the elevator under the following conditions: (a) The elevator is accelerating upward at 12 ft/sec2. (b) The elevator is accelerating downward at 12 ft/sec2. (c) The elevator is accelerating downward at 32 ft/sec2. Have we made any restrictions on the directions of the velocity in parts (a), (b), and/or (c)? If so, what?

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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