Engineering Statics


A tension of 5 lb. is maintained in a tape as it passes the support system shown. Knowing the radius of each roller is .4 inches, determine the reaction at point C.

The moment equation about point C allows to avoid the two 
forces at C and solve for the moment at C.  Remember that a 
built-in member has three reactions, two forces and a moment!
The negative sign for the moment indicates a clockwise 
The force equation in the x-direction allows us to solve 
for a single unknown.
Solving for F<sub>x</sub> gives us a force to the left.
Now the force equation in y direction only has one 
Solving, gives us an upward force at F.