What Is the Maximum Mass That Keeps Truss Forces Within Limits?

AI Thread Summary
The discussion revolves around determining the maximum mass of a suspended block while ensuring that the forces in any truss member do not exceed specified limits of 52 kN (tension) and 47 kN (compression). The user expresses frustration with the lack of comprehensive examples and explanations in their physics textbook, Hibbeler, which complicates their understanding of the problem. They mention using equilibrium equations for moments and forces to solve for the mass. Additionally, they inquire about analyzing specific joints if certain points were hinged to a wall. The conversation highlights challenges faced in learning and applying physics concepts effectively.
JJRKnights
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Homework Statement


24zvji1.jpg

Determine the largest mass m of the suspended block so that the force in any member does not exceed 52 kN(T) or 47 kN(C).

Homework Equations


ƩM = 0
ƩFy = 0
ƩFx=0

The Attempt at a Solution


6gfsip.png

Did I assume the arrows right?

Would this be the right track to solving this?
Solve for each piece.
Sum of moments, and solve for m?
 
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Using Hibbeler as my book, no relevant examples in the book(as always), not enough explanation to solve the questions(as always). All the physics books I've ever encountered are so incomplete that I'm surprised they get published. If I never did physics, picked up one of these books and tried to learn it from the start, I'd probably get stuck in the first chapters because of the lack of explanation. My professor is even worse, let's give extremely easy examples, but when it comes to problems let's make them extremely hard.
 
All the back of the book says is:

Joint D: (F_DC)sin45 + (F_DE)cos30.25 - W = 0
Joint A: F_AG - 1.414Wsin45 = 0

Thanks for the detail Hibbeler.
 
JJRKnights said:
Using Hibbeler as my book, no relevant examples in the book(as always), not enough explanation to solve the questions(as always). All the physics books I've ever encountered are so incomplete that I'm surprised they get published. If I never did physics, picked up one of these books and tried to learn it from the start, I'd probably get stuck in the first chapters because of the lack of explanation. My professor is even worse, let's give extremely easy examples, but when it comes to problems let's make them extremely hard.

If points E and C were attached/hinged to a wall, could you analyse CD and ED.
The scale of the diagram will show you how far apart E and C are - there is a 45o angle in there.
 
Solved it
 
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