Lifting a 3m Beam: Calculating Force, Friction, & Net Force

AI Thread Summary
A construction worker is lifting a 3.00 m beam weighing 372 N to a vertical position, applying a perpendicular force F while holding it at a height of 1.50 m. The discussion focuses on calculating the magnitude of the force exerted by the worker, the net force of the floor on the beam, and the minimum coefficient of static friction required to prevent slipping. The worker's confusion primarily revolves around understanding the net forces acting on the beam, particularly in part B of the problem. The calculations involve resolving the forces into components and applying equilibrium conditions to find the required values. The thread concludes with a realization that the problem, while initially complex, can be simplified through systematic analysis.
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[mentor note: moved here from another forum, hence no homework template.]

A construction worker attempts to lift a uniform beam off the floor and raise it to a vertical position. The beam is 3.00 m long and weighs 372 N. At a certain instant, the worker holds the beam momentarily at rest with one end at distance d = 1.50 m above the floor by exerting a force F on the beam, perpendicular to the beam. (a) What is the magnitude F? (b) What is the magnitude of the (net) force of the floor on the beam? (c) What is the minimum value the coefficient of static friction between beam and floor can have in order for the beam not to slip at this instant?

(The worker is lifting the beam from one end of the beam)
 
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My problem comes in part B. I tried to find the components of the force and the weight of the beam and combine them (since the worker will lift the beam, I assume that the floor will have less force on it since the worker will hold some of the total force). I am confused on part B since I am also not really sure what is asking for
 
oh I got IT! by myself xp, I fnetx=Fx-127cos(52.88)=0. fnety=Fy-mg+127(sin52.88)=0. Solve for Fx and Fy and use get the magnitude!. Hope this helps if anyone ever encounter this problem, took me 2 hours :(! so simple though (For Part B)
 
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