How Do You Calculate Resultant Forces in a Parallelogram of Forces?

  • Thread starter Thread starter manich43
  • Start date Start date
  • Tags Tags
    Forces
Click For Summary
To calculate resultant forces in a parallelogram of forces, the component approach is recommended, where each force vector is broken down into its x and y components. By expressing the forces as Fv1 = fx1 i + fy1 j, Fv2 = fx2 i + fy2 j, and Fv3 = fx3 i + fy3 j, the resultant force can be found by summing the i and j components. The law of vector addition applies, allowing for the construction of a vector triangle or parallelogram to visualize the forces. This method effectively demonstrates that the resultant force can be determined from the combined components. Understanding this approach simplifies the calculation of resultant forces in physics problems.
manich43
Messages
5
Reaction score
0
Can someone show me how to calculate the resultant forces shown as RF N and R F 1on the attachment please, in simple terms.



2.I need to work out the following..."Three forces applying to one point,find the resultant force" (magnitude and direction to horizontal line) R F1 and R F N



3.Any help greatly appreciated.

Mark
 

Attachments

Physics news on Phys.org
Welcome to PF.

The approach that works best for me is the component approach.

What you have is a vector addition in x,y

So try taking each Force vector as

Fv1 = fx1 i + fy1 j
Fv2 = fx2 i + fy2 j
Fv3 = fx3 i + fy3 j

Then just add the i's and the j's and you have your resultant

F = (fx1+fx2+fx3) i + (fy1+fy2+fy3) j
 
Hi,
Dont really follow that.This is the first time i have seen a parallelogram of forces.Can you explain how I would find the resultant force in N for RF 1 and RF N on the diagram.

Many Thanks...Mark
 
Welcome to PF!

manich43 said:
This is the first time i have seen a parallelogram of forces.Can you explain how I would find the resultant force in N for RF 1 and RF N on the diagram.

Hi Mark! Welcome to PF! :smile:

Forces are vectors, so they obey the law of vector addition …

that means that to add two vectors, you slide one so that it starts where the other one ends

in other words, you make a vector triangle …

but it comes out the same if you start both of them from the same point, and make a parallelogram (as in your diagram) …

to convince yourself that they're the same, just try sliding one of the sides of the parallelogram along to the opposite side :wink:
 
Thanks to all who replied,problem solved!

Mark
 
Thread 'Correct statement about size of wire to produce larger extension'
The answer is (B) but I don't really understand why. Based on formula of Young Modulus: $$x=\frac{FL}{AE}$$ The second wire made of the same material so it means they have same Young Modulus. Larger extension means larger value of ##x## so to get larger value of ##x## we can increase ##F## and ##L## and decrease ##A## I am not sure whether there is change in ##F## for first and second wire so I will just assume ##F## does not change. It leaves (B) and (C) as possible options so why is (C)...

Similar threads

  • · Replies 11 ·
Replies
11
Views
1K
Replies
4
Views
1K
Replies
17
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 7 ·
Replies
7
Views
1K
  • · Replies 30 ·
2
Replies
30
Views
2K
Replies
4
Views
2K
Replies
3
Views
1K
  • · Replies 14 ·
Replies
14
Views
3K
Replies
3
Views
1K