> OF FOI 



(2) Let fall within the AC or ' 



>sitc anj_ r 



Therefore 



that is, the moment of AD= the moment of 

 moment of AB. As the moments of A C and AD about 

 an- now of opposite characters, the moment of the resultant 

 is still equal to the algebraical sum of the moments of the 

 components. 



The proposition may also be readily shewn in the 

 where the two component forces are parallel; see Art. 37. 



In this example, however, nothing is gained in brevity or 

 simplicity by the aid of Geometry; for the required result is 

 an immediate consequence of the mechanical principle, that the 

 resolved part of the resultant along a straight line throu 

 at right angles to AO is equal to the algebraical sum of the 

 resolved parts of the components in the same direction. 



G3. Forces are represented itmJr, and i>< 



the sides of a plane polygon taken in order ; required tl 

 suit" 



Let the sides of the figure ABCDEF represent the forces 

 in magnitude and position ; the first force being suppo. 



