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1. The vertical external forces at A, C, D, E and
F represent the effect of the roof materials.
The force at B represents wind force on the
roof. Solve the problem with symbols for
loads and lengths; use numbers given for
angles.
a. Draw a free-body-diagram of the truss,
and find the reactions at the supports at A
andF.
b. Determine the axial forces in the truss
members DE, GE and GF.
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2. The frame/machine shown in the figure is loaded by a
force L and a moment M. The member DE is a quarter
circle.
a. Draw proper free body diagrams of the all the
members
b. Identify the two-force members and indicate the
direction of the force in these members.
c. Given the values of the load and the dimension R,
for what value of the moment M will the force in
the member CHbe zero?
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