What Is the Tension in the Right End Cable of Scaffold 1?

AI Thread Summary
The discussion focuses on calculating the tension in the right end cable of a horizontal scaffold system. The system consists of two scaffolds with specific masses and a box of nails positioned on the lower scaffold. The user initially labeled the tensions and set up torque equations to solve for the unknown tensions. After some calculations, the user identified an error in their final equation, where they mistakenly switched two tension variables. The correct approach involves careful attention to the labeling and application of torque equations.
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Homework Statement


A horizontal scaffold 2, with uniform mass m2 = 30 kg and length L2 = 2.4 m, hangs from horizontal scaffold 1, with uniform mass m1 = 53 kg. A 21 kg box of nails lies on scaffold 2, centered at distance d = 0.45 m from the left end, which is located from 0.45 m from the left end of horizontal scaffold 1 (same for the right end). What is the tension T in the right end cable of horizontal scaffold 1?


Homework Equations


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The Attempt at a Solution


First of all, I labeled the Tensions T_1, T_2, T_3, and T_4. T_1 is the top left, T_2 is the top right, T_3 bottom left, T_4 bottom right.

Then the Torques which I will call t are the following:

t_net,3 = d*m_b*g - 1/2 L*m_2*g + LT_4 =0
The unknown in this equation is T_4, so I solved for T_4.

Next:
t_net,4 = -L*T_3 + m_b*g*(L-d) + 1/2 L*m_2*g = 0
I solved for T_3.

Finally, I used:
t_net,1 = -T_3*d - (d+(L/2))*m_1*g - T_4(L+d) + T_2 (2d+L) = 0
to solve for T_2.

I found the answer to be 556.3727 N; however, it is apparently wrong.
 
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Oh nevermind, I see what I did. I was accidently switching T_3 and T_4 when plugging them into the final equation.
 
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