Skip to main content
P
ptc-48686551-Visitor
1-Visitor
November 13, 2014
Solved

Three equations in three unknowns

  • November 13, 2014
  • 6 replies
  • 3049 views

Hello!

How can I find symbolically the ex,ey and Phi variables? I have tried with solve block, but the solution was the guess value.

See the 3 equations in the attachment

Thanks in advance!

Best answer by RichardJ

Like so

HF6.png

6 replies

V
ValeryOchkov24-Ruby IV
24-Ruby IV
November 14, 2014

Do you try to solve one kynematic

http://communities.ptc.com/groups/kinematic-models-in-mathcad

or dynamic

http://communities.ptc.com/groups/dynamic-models-in-mathcad

problem?

P
ptc-48686551-VisitorAuthor
1-Visitor
November 14, 2014

This is a static problem, to find the S1-S4 reaction forces of the statically indeterminate structure with energy method.

Werner_E
Werner_E25-Diamond I
25-Diamond I
November 14, 2014

If you write equations to solve you have to use the boolean equal sign.

If you use the solve block you will not only have to provide guess values for the variables you want to solve for but must provide values for all variables used.

In Prime (in contrary to Mathcad) a solve block ist only to be evaluated numerically.

What should the three pi's represent?

constants? Then you just have two equations.

functions? Then you have no equation at all

BTW. I noticed that you still have a lot of your questions marked as "Not Answered". You seem to tend to ask but don't come back again to comment the replies given.

P
ptc-48686551-VisitorAuthor
1-Visitor
November 14, 2014

The tree Pi represents the inner, outer and total energy, and it is the force times the distance the object is moved

I'm sorry if I don't hit the correct answer button, but I really appreciate yours help. Thank you all!

Werner_E
Werner_E25-Diamond I
25-Diamond I
November 14, 2014

I got confused because you defined your functions kappa like variables (which works because you use the symbolics) and so guessed wrong as of the equations you want to solve.

Fortunately Richard was around and guesewd right.

You can also use the derivatives in the solve statement:

1.png

A numeric solve block should work, too. But here you would have to define your functions correctly as functions (kappa(ex,ey,phi):=....) and provide values for all constants as well.

R
RichardJ19-TanzaniteAnswer
19-Tanzanite
November 14, 2014

Like so

HF6.png

Terms & ConditionsAccessibility statement