- #1
jonjacson
- 453
- 38
Homework Statement
I´ll show it with a picture:
Homework Equations
Static equilibrium, Sum Forces=0 ; Sum Moments= 0
The Attempt at a Solution
With the Fx, and Fy equations I can calculate the reactions Rx and Ry but I don´t understand the moments equation:
Sum M around point O =0= 1,4*1,2 + 15 - 3* cos(30)*4.8 = 4,2 KN m = 0
I didn´t use the moments of the reactions at O because I thought that their moment arms were zero, but in that case I get an equation that doesn´t have any sense.
I can calculate the moments of the forces to the point O, and I can add the 15 Knm, but the point is in order to get equilibrium Should I consider the moments of the reaction forces at O? In that case why the problem is not giving me any data about the lenghts x,y,z that I showed near O?