B Will there be a reaction at the hinge B in this question?

AI Thread Summary
The discussion centers on the question of whether a reaction at hinge B is necessary for solving a mechanics problem. The original poster found that ignoring the reaction at hinge B still led to a correct answer, suggesting that half of the weight of rod AB is effectively supported by B without affecting the outcome. Participants express curiosity about the reasoning behind this observation, questioning if it is merely a numerical coincidence or if there is a logical explanation. The complexity of the problem is acknowledged, with six unknowns and three equations of statics involved. Ultimately, the conversation highlights the importance of understanding the roles of various forces in static equilibrium.
Asad Raza
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I have solved this question by completely disregarding the reaction at the hinge B. And surprisingly, answer turns out to be correct. Why is that so?
 

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Half the weight of AB is on B (AB doesn't rotate or move) and that gives you the ##13\over2##.

For the second part I'm too lazy to work it out (you did that already); if you post your work, I (or someone else) may comment (e.g: "it doesn't matter" or "it's a numerical coincidence") :smile:
 
How do we know that half of AB's weight is on B?
 
You have 6 scalar unknowns: two components of each reaction force at the points A,B,C. You also have three equations of statics for each rod. I wish you good luck
 
zwierz said:
You have 6 scalar unknowns: two components of each reaction force at the points A,B,C. You also have three equations of statics for each rod. I wish you good luck
But Reaction at B isn't playing a role. Just explain it to me that whether is that a coincidence or there's some solid logic behind?
 
How can I explain if you already know what plays role here and what does not? :)
 
This should be posted in a homework forum, with an attempt at a solution.

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