What is the tension in the rope DE?

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    Rope Tension
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The problem involves a ladder hinged at point A with a rope DE tied halfway up, supporting a weight of 40 kg suspended from point F. The normal forces at points A and B are calculated as 250 N and 150 N, respectively, using torque equations and equilibrium conditions. The challenge lies in determining the tension in rope DE, as the moments from the normal forces cancel each other out. To find the tension, constructing free body diagrams for the ladder's legs is necessary, ensuring that both legs are in rotational equilibrium. The discussion concludes with the user successfully resolving the tension issue after further analysis.
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Homework Statement


WIN_20150224_115138.JPG

AB = AC =1.6m, hinged at A. a rope DE of length 0.5m is tied half way up.
A weight of 40Kg is suspemded from F 1.2m from A. Assuming frictionless floor and negligible mass of the ladder Find the tension in the rope DE.

Homework Equations


torque[/B] = Force × perpendicular distance

The Attempt at a Solution


##N_band N_c## are the normal forces at A and B.
if i take the net moment about A:
##N_b d_1 - 400d_2 = N_cd_1##
also
##N_b +N_c = 400N##
Solving these equations an using the ratio ##\frac{d_1}{d_2}##
I get ##N_b = 250N and N_c=150N##
this corresponds to the answer given for ##N_b and N_c##
But how do i find out the tension, their moments get canceled out!
 
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Once you have solved for Nb and Nc, you should be able to construct free body diagrams for the legs AB and AC.

Since the whole ladder is in equilibrium, each leg must be in equilibrium as well.
 
Rotational equilibrium?? i tried that and got 2 equations with 3 variables.
EDIT: Got it thank you!
 
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