Finding unknown values within matrices
Finding unknown values within matrices
(OP)
Good morning all.
I'm having the following problem:
I'm trying to find given pressures at which a resultant force will equal 0lbs, however, the two pressures that affect the resultant force act in different directions but are related to each other. To simplify my problem, I am trying to achieve values for P1 below.
F-((A1*P1)-(A2*P2))=0
where:
A1= 10in^2
A2= 5in^2
F= matrix with 6 rows, 1 column (known values say 100-600 lbs)
P2= P1-300psi ( will be a matrix with 6 rows, 1 column as a result of P1)
P1 must therefore be a matrix with 6 rows and 1 column.
I have tried using the given and find method and the soln but they don't seem to work. Finding P1 for all six values of F would maybe not be too hard to do individualy however, I'd like to learn how to do it in one go. I have tried MathCad books but still haven't found an example like this.
Thanks in advance.
I'm having the following problem:
I'm trying to find given pressures at which a resultant force will equal 0lbs, however, the two pressures that affect the resultant force act in different directions but are related to each other. To simplify my problem, I am trying to achieve values for P1 below.
F-((A1*P1)-(A2*P2))=0
where:
A1= 10in^2
A2= 5in^2
F= matrix with 6 rows, 1 column (known values say 100-600 lbs)
P2= P1-300psi ( will be a matrix with 6 rows, 1 column as a result of P1)
P1 must therefore be a matrix with 6 rows and 1 column.
I have tried using the given and find method and the soln but they don't seem to work. Finding P1 for all six values of F would maybe not be too hard to do individualy however, I'd like to learn how to do it in one go. I have tried MathCad books but still haven't found an example like this.
Thanks in advance.





RE: Finding unknown values within matrices
DO you want the obvious solution?
P1:(F+300*A2)/(A1+A2)
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Finding unknown values within matrices
I've spent so long looking at it on the MathCad screen which is covered in matrices and funtions that contain umpteen terms that I was confusing myself to think it's more complicated than it is.
Looking at the original post it is actually quite obvious I'll take it as a lesson learned to use a pen and paper and simplify things right down in the future. Why It didn't click in my brain as I typed it out I don't know?
Thanks for pointing that out.
RE: Finding unknown values within matrices
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.