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1-Visitor
August 28, 2018
Solved

How to find radius vector of force by given force and moment

  • August 28, 2018
  • 5 replies
  • 3002 views

M=r x F

how to find vector r if F and M are defined

Thanks in advance

Best answer by ifomenko

Thank you all, this picture illustrate your answers in 2D

COG.PNG

Sorry for this stupid question

5 replies

25-Diamond I
August 28, 2018

There is no single, unique solution.

Normally you will have one degree of freedom and the solution may depend on one parameter.

The expression below may be simplified if we could assume that the scalar product of M and F is zero.

Unfortunately Mathcad won't let me add that assumption.

B.png

ifomenko1-VisitorAuthor
1-Visitor
August 28, 2018

There is a unique solution - it is a center of gravity point, for example.

25-Diamond I
August 28, 2018

@ifomenko wrote:

There is a unique solution - it is a center of gravity point, for example.


I guess not, if all you have is moment and force vector.

Can you provide an example.