一道英文物理题A sign has a mass of 1050 kg,a height h = 1 m,and a w

一道英文物理题

A sign has a mass of 1050 kg,a height h = 1 m,and a width W = 4 m.It
is held by a light rod of length 5 m that is perpendicular to a rough
wall.A guy wire at 23° to the horizontal holds the sign to the wall.
Note that the distance from the left edge of the sign to the wall is 1
m.


Suppose we rely upon friction between the wall and the rod to hold up
the sign (there is no hinge attaching the rod to the wall).What is the
smallest value of the coefficient of friction μ such that the sign will
remain in place?