Physics lab report calculating resultant forces -- help please

AI Thread Summary
The discussion revolves around a physics lab report focused on calculating resultant forces from vector addition. The user is struggling to articulate their experiment due to a language barrier, having transitioned from learning physics in Russian to English. They mention that the experiment involves two forces, F1 and F2, which must counterbalance a downward force, Fg. Participants suggest clarifying the experiment's details and provide guidance on how to calculate the resultant force through vector addition. The conversation emphasizes the importance of accurately representing vector directions and applying the correct equations for the calculations.
DanchoSuper
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Homework Statement
I need to finish physics lab report. I tried doing it and teacher said that i have a lot of mistakes
Relevant Equations
Fx=Fcosa
Fy=Fsina
i have attached my attempt above i have sent it to my teacher and he said i should fix the mistakes and resend it
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Welcome to PhysicsForums. :smile:

It's a bit hard to follow all of that. Could you please describe in words what the experiment is all about, how you did it, and what your results were? It's a bit hard to tell the difference between what are the questions and what parts are your work/answers. Thanks.
 
We didn't do the experiment because we're having online classes. Teacher said that the results are already given and we just need to complete it.
 
It's really hard to explain because I was taught Physics in russian previously for 4 years starting from 7th grade to 10th grade. But starting from this year we are taught Physics in English.
 
DanchoSuper said:
It's really hard to explain because I was taught Physics in russian previously for 4 years starting from 7th grade to 10th grade. But starting from this year we are taught Physics in English.
maybe you can upload a picture of the description of the experiment/question if you are having trouble explaining it?
 
Screenshot_2020-09-17-22-09-45-390_com.microsoft.teams.jpg

I think it's about vectors and there are two forces and we have to find the resultant vector
 
DanchoSuper said:
I think it's about vectors and there are two forces and we have to find the resultant vector
Welcome, DanchoSuper! :cool:

Yes, the lab is about addition of vector forces.
What do you know about that?
What is that you don't understand?

Please, see:
http://hyperphysics.phy-astr.gsu.edu/hbase/vect.html#vec1

In order to keep the weight suspended in the air, forces F1 and F2, pointing up at certain angle (the V shape of the fish scales between both vertical supports) must compensate for Fg pointing vertically down.
The vectorial addition of F1 and F2 equals a ficticious force pointing straight up, which magnitude is exactly the same as Fg, but of opposite sign (oposite direction).

I can't see it well enough (sorry, I am old and half blind), but I believe that you have incorrectly represented the directions of vectors F1 and F2: they should look like a ∨ (heads up/tails down) instead.

The steps indicated in the lab should show you how the values of F1and F2 become greater and greater rapidly as the angle of the V-shape increases (as you separate both vertical supports from each other).
CNX_UPhysics_06_01_StopLight.jpg
 
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So how to find the resultant force
 
DanchoSuper said:
So how to find the resultant force
You use the relevant equations that you showed in your first post.
After measuring F1 and F2 for each angle, you calculate F1x, F1y, F2x and F2y.
Then, you do the vector additions of F1y + F2y, as shown in above link.
 
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