Problem 2 A load is to be raised 12 ft by the hoisting system shown, developed by ASCE Club students to lift various loads to the ceiling of the Construction Materials Laboratory. Assume gear A is initially at rest, then accelerates uniformly to a speed of 110 rpm in 5 s, and then maintains a constant speed of 110 rpm. Gear A has radius r = 4.0 in, gear B has radius r = 22 in, and drum C has radius rc = 18 in. Drum C rotates with gear B. Determine: (a) the number of revolutions executed by gear A in raising the load, (b) the time required to raise the load to 12 ft.

Problem 2 A load is to be raised 12 ft by the hoisting system shown, developed by ASCE Club students to lift various loads to the ceiling of the Construction Materials Laboratory. Assume gear A is initially at rest, then accelerates uniformly to a speed of 110 rpm in 5 s, and then maintains a constant speed of 110 rpm. Gear A has radius r = 4.0 in, gear B has radius r = 22 in, and drum C has radius rc = 18 in. Drum C rotates with gear B. Determine: (a) the number of revolutions executed by gear A in raising the load, (b) the time required to raise the load to 12 ft.

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 7.57P: The square-threaded screw with a pitch of 10 mm and a mean radius of 18 mm drives a gear that has a...

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