Drawing Free Body Diagrams for rope tension

[tascja]

Homework Statement

A man of mass 64.2 kg stands on a scaffold supported by a vertical rope at each end. The scaffold has a mass of 23.2 kg and is 3.2 m long. Suppose the man stands to the right from the middle of the scaffold that is a distance one sixth of the length of the scaffold. What is the tension in the right rope? What is the tension in the left rope?

The Attempt at a Solution

im always confused on how exactly to draw out the scenarios and start the question. For this particular problem i got this far:
1. straight bar for scaffold with an arrow pointing down, half way (the center of gravity)
2. a man closer to the right rope, with an arrow pointing down, (his weight F=mg)
3. the two ropes on either side are tension (arrows pointing up)

Now I am not sure if there would be torque, because one rope has more force than the other, if so where would the pivot point be?? or if i should some how solve it be equating the tensions since the system is static??
Help would be greatly appreciated

 

[LowlyPion]

If it is in equilibrium (it is), then the ∑ F and the ∑ T are both 0.

So choose an end and balance out the torque.

 

[tascja]

so the torque applied (right rope) = torque(scaffold) + torque(man)
Fr = Fr + Fr
Fr = (23.2)(9.81)(3.2/2) + (64.2)(9.81)(3.2*2/3)
F = 1707.7/3.2
F = 533.66 N
so the tension in the right rope is 534 N??

 

[LowlyPion]

I suppose you mean that

∑ F = 0 = T_l + T_R - ∑ m*g

You should have the equation for the torque about end the man is farthest from.

And that should solve for the T of the rope he is closest to - the right Tension. And your answer looks OK.

Then you can figure the other tension directly from the first ∑ F.