3. Three kids stand on a see-saw as shown. The see-saw has a uniform cross section and weighs 10 lb, while kids A, B, and C weigh 30 lb, 40 lb, and 20 lb, respectively. Determine the weight of the rock at point E required for the system to maintain a perfect balance, and the reaction at support D. Write your answers using 3 significant digits. В A C k 1 ft * 1 ft ** 7.5 ft 0.5 ft

3. Three kids stand on a see-saw as shown. The see-saw has a uniform cross section and weighs 10 lb, while kids A, B, and C weigh 30 lb, 40 lb, and 20 lb, respectively. Determine the weight of the rock at point E required for the system to maintain a perfect balance, and the reaction at support D. Write your answers using 3 significant digits. В A C k 1 ft * 1 ft ** 7.5 ft 0.5 ft

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

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter5: Three-dimensional Equilibrium

Section: Chapter Questions

Problem 5.39P: The bent rod of negligible weight is supported by the ball-and-socket joint at B and the cables...

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