Hi there. This problem is very basic but I really cannot figure out how to solve it. I'm missing something but I have no clue what it is.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Three forces act on a moving object. One force has a magnitude of 80.0 N and is directed due north. Another has a magnitude of 60.0 N and is directed due west. What must be the magnitude and direction of the third force, such that the object continues to move with a constant velocity?

2. Relevant equations

Force X Y

F1 F1Cos90 F1Sin90

F2 -F2Cos90 F2Sin90

W 0 -W=-mg

3. The attempt at a solution

F1Cos90-F2Cos90+0=0 (Then divide by Cos90)

F1=F2=>F

FSin90+FSin90=mg

2FSin90=mg

F=mg/2(Sin90)

F=mg/2(1)

F=mg/2

I would be very thankful if someone could please tell me what I'm doing wrong and what I should be doing so that I may learn from this question.

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# Homework Help: Equilibrium at Constant Velocity

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