Newton's Laws and finding magnitude

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An object with a mass of 1.25 kg is subjected to two horizontal forces, F1 and F2, with F1 having a magnitude of 26.75 N and the object accelerating at 9.3 m/s². To find the magnitude of F2, Newton's second law is applied, resulting in the equation F_total = ma. The total force acting on the object is calculated, leading to the conclusion that F1 minus F2 equals the product of mass and acceleration. The correct calculation shows that F2 is approximately 15.09 N, confirming the relationship between the forces. The discussion emphasizes the importance of accurately applying Newton's laws to solve for unknown forces.
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An object of mass 1.25 kg on a flat surface has two forces acting on it, F1 and F2 in the horizantal direction. F1 acts in the positive direction, F2 acts in the negative direction. The magnitude of F1 is 26.75 N. The object moves strictly along the horizontal x-axis, which we choose as positive to the right. Find the magnitude of F2 if the object has a horizontal acceleration of 9.3 m/s2.



No clue where to start. Any help would be great !
 
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hi physics_10! :wink:

use good ol' Newton's second law … Ftotal = ma …

what do you get? :smile:​
 
11.63 N. so that's it? I don't need to do anything with F1?
 
(try using the X2 icon just above the Reply box :wink:)
physics_10 said:
11.63 N. so that's it?

no, that would be the value of F2 if F2 was the total force

try again :smile:​
 
Is it F1-F2..
so 26.72-11.63 = 15.09 N?
 
physics_10 said:
Is it F1-F2..
so 26.72-11.63 = 15.09 N?

that's right!

Ftotal = F1 + F2 = 26.72-11.63, and that has to equal ma. :smile:

(but is it 26.72 or 26.75?)
 

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