Holding Up a Sign: Static Equilibrium Force and Torque

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To maintain static equilibrium for the sign and vertical post system, the external forces and torques must balance. The sign has a mass of 1.80 kg and the post has a mass of 4.16 kg, with the sign hanging symmetrically. The torque equation should be set up as Torque = F1d1 - F2d2 - Fd3 = 0, where F represents forces and d represents distances from the pivot point. A free body diagram is recommended to visualize the forces acting on the system, including the unknown vertical reaction force (V) and torque (T) at the hand. Properly applying equilibrium equations will allow for solving these unknowns effectively.
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Homework Statement


You are holding a sign as shown below. The sign (including the horizontal bar it hangs from) has a mass of 1.80 kg and is 36.5 cm wide. The sign is hanging from a 1.30 m tall, 4.16 kg vertical post. The sign is symmetric with a uniform mass distribution as implied by the drawing.
Q0vSIDa.png

What external force (+ if up, - if down) and torque (+ for CCW, - for CW) do you have to apply with your hand to keep the sign in static equilibrium? [Use g = 9.80 m/s2 and ignore the width of the vertical post.]

Homework Equations


Torque = Fd = 0

The Attempt at a Solution


I'm not quite sure how to deal with the vertical stick.
Torque = F1d1 - F2d2 - Fd3 = 0
As far as the set up goes, this is all I've got and I don't think it is correct. I may not be visualizing this problem correctly.
 
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PierceJ said:

Homework Statement


You are holding a sign as shown below. The sign (including the horizontal bar it hangs from) has a mass of 1.80 kg and is 36.5 cm wide. The sign is hanging from a 1.30 m tall, 4.16 kg vertical post. The sign is symmetric with a uniform mass distribution as implied by the drawing.
Q0vSIDa.png

What external force (+ if up, - if down) and torque (+ for CCW, - for CW) do you have to apply with your hand to keep the sign in static equilibrium? [Use g = 9.80 m/s2 and ignore the width of the vertical post.]

Homework Equations


Torque = Fd = 0

The Attempt at a Solution


I'm not quite sure how to deal with the vertical stick.
Torque = F1d1 - F2d2 - Fd3 = 0
As far as the set up goes, this is all I've got and I don't think it is correct. I may not be visualizing this problem correctly.
There is an external unknown vertical reaction force and an unknown torque at your hand. You should identify these as V and T, respectively. Now apply your equilibrium equations to solve for them. Although explain what F1 ,d1 ,etc. are.
 
How about starting with a free body diagram?
 
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