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ok, i don't know why, but this question has been baffling me since morning
we have two supports both with reactions in x- and y-directions (in 2D), and one external load. now i have tried this with two sets of variables, but the problem i am facing is that in both cases i am getting different answers for different sets of equations.
The problem is something like this:
I have a load W acting at pt C (W can be assumed at say 330N) in negative y direction
and i have supports at pts A and B, which are: Ax, Ay,Bx and By, all are not known.
assuming all reactions are in positive x- and y- directions
Now i can get these equations:
Ax = -Bx as no other horizontal forces are there
also Ay + By = W
from equilibrium of forces
and
then obviously three equations from the equilibrium of moments at point A, B and C respectively. (all distances are known)
since there are four variables, i am feeding these to an equation solver software
however, the software rightly says that the problem is over-specified with 5 equations and 4 variables
but, when i try to run it with any four of the the five equations, each time i get a different answer...which is the problem because i think, it should give the same answer from any randomly chosen four equations...no?
what am i doing wrong here?
we have two supports both with reactions in x- and y-directions (in 2D), and one external load. now i have tried this with two sets of variables, but the problem i am facing is that in both cases i am getting different answers for different sets of equations.
The problem is something like this:
I have a load W acting at pt C (W can be assumed at say 330N) in negative y direction
and i have supports at pts A and B, which are: Ax, Ay,Bx and By, all are not known.
assuming all reactions are in positive x- and y- directions
Now i can get these equations:
Ax = -Bx as no other horizontal forces are there
also Ay + By = W
from equilibrium of forces
and
then obviously three equations from the equilibrium of moments at point A, B and C respectively. (all distances are known)
since there are four variables, i am feeding these to an equation solver software
however, the software rightly says that the problem is over-specified with 5 equations and 4 variables
but, when i try to run it with any four of the the five equations, each time i get a different answer...which is the problem because i think, it should give the same answer from any randomly chosen four equations...no?
what am i doing wrong here?