How do I find the intersection of the wrench's LOA?

AI Thread Summary
The discussion focuses on finding the intersection of a wrench's line of action (LOA) in a 3D force system. The user has calculated the moment using the cross product but is uncertain about applying this to determine the intersection point on the yz plane. Clarification is sought on the meaning of LOA, which is identified as the line of action of the force. Additionally, there is confusion regarding the different forces mentioned, and the need for a clear representation of the forces is emphasized. A suggestion is made to refer to a video for a better understanding of the method.
daisy7777
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Homework Statement
A thin rectangular flat plate is loaded by the forces show. Determine a wrench equivalent force system, and specify the y and z coordinates of the point where the wrench's LOA intersects the yz plane.
Relevant Equations
M = Fd
M = r xF
I've solved for the moment using the cross product where my r = 0i+0.06j+0.03k m and my F = 100i + 150j + 0k. I got my moment to be M= 4.5,3,-6. I know a wrench equivalent force must be parallel to the force (I am assuming this means the resultant force in this case), but how do I apply that logic to fid the intersection? I assume I am meant to use the formula M=Fd where F = 300i, 0j, 0k but I am not sure if this is even applicable in this question as it is in 3D.

All in all, I would just like a little push in the right direction.
 
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daisy7777 said:
Homework Statement: A thin rectangular flat plate is loaded by the forces show. Determine a wrench equivalent force system, and specify the y and z coordinates of the point where the wrench's LOA intersects the yz plane.
Relevant Equations: M = Fd
M = r xF

I've solved for the moment using the cross product where my r = 0i+0.06j+0.03k m and my F = 100i + 150j + 0k. I got my moment to be M= 4.5,3,-6. I know a wrench equivalent force must be parallel to the force (I am assuming this means the resultant force in this case), but how do I apply that logic to fid the intersection? I assume I am meant to use the formula M=Fd where F = 300i, 0j, 0k but I am not sure if this is even applicable in this question as it is in 3D.

All in all, I would just like a little push in the right direction.
Since you have not posted the details of the question, it is impossible to check your work. In particular, you do not explain how you obtained that vector for r.
 
daisy7777 said:
the point where the wrench's LOA
Sorry, what is LOA in this context?

https://www.abbreviations.com/LOA
 
@daisy7777, note what @haruspex said in Post #2. And a diagram is needed.

You have written "F = 100i + 150j" + 0k and "F = 300i, 0j, 0". If you are referring to two different forces the meaning of each must be clear and they should have different symbols.

If you are not familiar with the method, try watching the short (~5 mins) video here
 
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