Static - help me please =(?

A 55.0-kg person stands 2.0 m from the bottom of the stepladder shown in the figure.





FIGURE %26gt; http://img99.imageshack.us/img99/8996/fi...





A) Determine the tension in the horizontal tie rod, which is halfway up the ladder. Ignore the mass of the ladder and assume the ground is frictionless. [Hint: Consider free-body diagrams for each section of the ladder.]





B) Determine the normal force the ground exerts on the right side of the ladder.





C) Determine the normal force the ground exerts on the left side of the ladder.





D) Determine the force (magnitude) that the left side of the ladder exerts on the right side at the hinge on the top.





E) Determine the direction if this force.

Static - help me please =(?
I'll walk you through it:


Do B and C first: Use geometry to find her horizontal position. If she is 40% to the left, then the left side holds 60% of the weight and the right side holds 40% of the weight.





A: Draw the FBD of the left side of the ladder. You can solve the M=0 and F=0 equations now that you know the vertical reactions at the base and hinge.





D: combine the vertical pin reaction you found in B and the horizontal reaction in A.





E. Use trig on the horizontal and vertical pin reactions.
Reply:that's a tricky one
Reply:The ladder was broken into 3 members; the left, the right, and the cross. The freebody diagram resulted in 5 unknowns, therefore, 5 equations must be generated.


They are as follows.


--The left member;


Fy1+R*sin(theta)=W; summation of vertical forces


R*(cos(theta)*L1+sin(theta)*L2 ) -T*L5=W*L3;


Momemt equation about the base of the left member


--The cross member;


T'-T=0; summation of horizontal forces


--The right member;


R*cos(theta)-T'=0; summation of horizontal forces


Fy2-sin(theta)=0; summation of vertical forces


These equations solve simultaneously for;


T=111.068


R=308.521


Fy1=251.7


T'=111.068


Fy2=287.85


So the answers are;


a.) 111.068 N


b.) 287.85 N


c.) 251.7 N


d.) 308.521 N


e.) down and to the right, 68.9889 degrees off the horizontal