Where did I go wrong in finding the length x using the grabber-statics example?

AI Thread Summary
The discussion revolves around calculating the length x in a grabber-statics example, where the grabber must hold a box. The user initially derived two moment equations and combined them to find x but ended up with an incorrect result. They suspected a mistake related to the frictional force balancing the weight of the box and the normal force needed to create torque. After further analysis, they concluded that they had identified the error and arrived at the correct solution. The conversation highlights the importance of understanding the relationships between forces and torques in static equilibrium problems.
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Hello,

We should get the length x , when the grabber can just hold the box.

yTBz.png


I made two moment equations:

e[czech]{babel}%20M_{1}=\frac{G}{2\mu%20}*\sqrt{(l_{1}+l_{2})^{2}+(\frac{b}{2})^{2}}\end{align*}.gif


yle\begin{align*}\usepackage[czech]{babel}%20M_{2}=\frac{G}{2}*\sin%20\alpha%20*%20x\end{align*}.gif


Then I put them together into one equation:
mathtex.gif


And from that equation I found out x:
mathtex.gif
Unfortunately the result seems to be wrong. Can you please help me? Where I made the mistake?
 
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i think the frictional force balance the wight of the box.we have to give the normal force on the box that give rise to the friction by giving a torque to the grabber
 
I finally got it. Here is the solution.

Ehpw.png
 
Yes,that is the correct answer:smile:
 
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