Hello,

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

I made two moment equations:

Then I put them together into one equation:

And from that equation I found out x:

Unfortunately the result seems to be wrong. Can you please help me? Where I made the mistake?

$\Sigma M_H = 0$

$(x\sin \alpha)(\frac{1}{2}G) + \frac{1}{2}G(\frac{1}{2}b) = \dfrac{G}{2\mu_0}(l_1 + l_2)$

$x = \dfrac{2(l_1 + l_2) - \mu_0 b}{2\mu_0 \sin \alpha}$

Thank you very much sir!

It is the right solution and now when I have understood it, it looks so much simplier than before.