What Angle \(\phi\) Balances the Pulley in Static Equilibrium?

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msds1502
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Homework Statement


Mechanical diagram, rotated 90 degrees: a 50 lb block hangs from pulley B on cable ABC, with angle phi marked at B on both sides, a bar hinged at D at 60 degrees, and a spring from C to fixed point E.
(rotate picture 90 degree clockwise)
A 50 lb weight is supported by a wire attached to a pulley at point B. The Pulley rests on wire ABC. If the tension in wire ABC is equal to 70lb determine the angle [tex]\phi[/tex] necessary to keep point B in balance


Homework Equations


F=ks



The Attempt at a Solution



I Know there is some force acting from C to D. There is also some spring force acting from C to E. What I don't understand is how to model the FBD with the tension force ABC and 50lb weight at point C
 
msds1502 said:

Homework Statement


Mechanics diagram, rotated 90 degrees: pin B connects bar AB, a bar from pin A on a hatched support, and bar BC; a 50 lb block hangs from B on a line, angle phi marked at each bar, and bar CD pinned at D at 60 degrees to a horizontal support, with spring CE hanging from C to support E.
(rotate picture 90 degree clockwise)
A 50 lb weight is supported by a wire attached to a pulley at point B. The Pulley rests on wire ABC. If the tension in wire ABC is equal to 70lb determine the angle [tex]\phi[/tex] necessary to keep point B in balance


Homework Equations


F=ks



The Attempt at a Solution



I Know there is some force acting from C to D. There is also some spring force acting from C to E. What I don't understand is how to model the FBD with the tension force ABC and 50lb weight at point C
The problem is asking for the angle [tex]\phi[/tex] when the pulley is in equilibrium. Draw a free body diagram of the pulley only. The weight is given and the tension in the rope on each side of the pulley is give. So use Newton's first law in the x direction and in the y direction, to solve for the angle.