I with vector addition and subtraction

AI Thread Summary
The discussion centers around calculating a third force needed to keep an object balanced between two forces acting at angles. The user has correctly identified the need to analyze both horizontal and vertical components of the forces involved. They have subtracted opposing horizontal forces and added horizontal forces moving in the same direction to find the resultant. The proposed method for determining the third force involves ensuring it counteracts the net effect of the two existing forces. Clarification on the direction of the components in the diagram is sought, emphasizing the importance of accurate vector representation in the solution.
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Homework Statement



Alright so I have an object being pulled from two sides at an angle like the picture below. I want to figure out a third force that can be added to keep the object in the middle of the two sides.

347ifpw.jpg


Are the directions of the components I drew correct?

(There is an actual problem for this, I thought I'd put a more general question though)

Homework Equations



Vector addition and subtraction

The Attempt at a Solution



I found the horizontal and vertical components of both forces. I then subtracted the horizontal forces from each other because they were going in opposite directions, and added the horizontal vectors because they were going in the same direction. To find the third force, I used the equal but opposite vertical and horizontal forces and found the third net force...

I hope I explained this right :S
Please help me out by telling me if I'm doing this right?
 
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It depends which force is greater, and by how much.

I like to see that you posted a more general problem, though! It helps you a lot more this way.

If I'm not mistaken (not done this in a long time!), F_3 should be in the direction of the weaker force, and should be equal to F_stronger - F_weaker.
 
Thank you for your help :D

To add a little bit of detail, the problem that I'm looking at has a greater horizontal force on one side, and the greater vertical force on the other.

If I did
V1 - V2 = -V3 (where V1 is the greater vertical force)
and
H1 + H2 = -H3 (since horizontal forces..seem to be pointing the same way, I am adding)
Would F3 = the net force of -V3 and -H3?

Are the directions of my components pointing in the right direction in the diagram if the system is moving right?
Am I completely doing this wrong? :P
 
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