Calculating Resultant Force: Understanding the Error

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The discussion focuses on calculating the magnitude of a resultant force, specifically addressing the vector FR = <-180, 810, 180>. A user calculated vector F1 as <240, 416, -360> and subtracted it from FR to find vector F2, ultimately arriving at a magnitude of 789 lb. Confusion arises regarding the accuracy of the FRy component, with participants questioning whether it is indeed 810 as stated. The user realizes the error may stem from incorrect units rather than the calculations themselves. The conversation highlights the importance of verifying component values and unit consistency in physics problems.
Luongo
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1. If the resultant force acting on the hook is FR = <-180, 810, 180> what is the magnitude of F?



2. So basically i got F1 which is <240,416,-360> and subtracted this from FR and got vector F2 then i took the square of the components and square rooted getting 789lb. Why is this wrong? what am i doing wrong?



3. Please tell me why i got the wrong answer it should be right
 

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Hi Luongo! :smile:

I get 789 also. :redface:

(Are you sure it's 810 for FRy? It doesn't look like that in the diagram)
 
Luongo said:
1. If the resultant force acting on the hook is FR = <-180, 810, 180> what is the magnitude of F?



2. So basically i got F1 which is <240,416,-360> and subtracted this from FR and got vector F2 then i took the square of the components and square rooted getting 789lb. Why is this wrong? what am i doing wrong?



Tell us how'd you get F1_x and F1_y!? :rolleyes:
 
Altabeh said:
Tell us how'd you get F1_x and F1_y!? :rolleyes:


to get those two i got F' which is the angle perp to the F1_z component then used that as a coefficient
 
tiny-tim said:
Hi Luongo! :smile:

I get 789 also. :redface:

(Are you sure it's 810 for FRy? It doesn't look like that in the diagram)


Yes it's right, i got the units wrong...? DAMN MASTERING PHYSICS! crap... lol
 

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