Hi
Many years since I had some classes in physics regarding forces and
torque.
I have a sun-shield I have to mount on a wall, but I would like to be
able to calculate the forces on the mount on the wall
See drawing:
www.microdesign.dk/tmp/wall_mounting.jpg
The left drawing is the mount. One metalplate is mounted sligtly tilted
on the wall using two nails. A metal rod is welded in a right angle to
this one - and in the end of this rod a weight exerts a force F on the
metal rod.
The draing on the right is my free-force diagram. The force, F, is
converted to a torque Ma, that is in the middle of the mounting plate
L2. The rod has length L1
Torque Ma = F*Cos(alpha) * L1.
My problem is to calculate exactly the force on the upper nail. The
lower nail (point C) only supports the plate and the mount rotates
around this hinge.
Is the force on the upper nail (B) equal to:
Mb = Fb * L2 => Fb = Mb / L2?
Is that correct that even though the rod is welded at the middle of the
mount, the torque is reffered to point C (so that a torque on a
non-ridig object is translated to the end of the object?)
Hope you can help me :-)
Thanks
Klaus
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