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Newton's Second Law Particle Problem

  • Thread starter Seraph404
  • Start date
1. The problem statement, all variables and given/known data

While two forces act on it, a particle is to move at the constant velocity v = (3 m/s)i - (4 m/s)j. One of the forces is F1 = (2N)i + (-6N)j. What is the other force?


2. Relevant equations

Fnet = ma


3. The attempt at a solution

Well, I'm really just wanting a hint. I know that the acceleration is zero because the velocity is constant. So how do I use velocity to find the second force? Surely I'm missing something fundamental here. Once again, just a hint would be nice.
 

PhanthomJay

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

While two forces act on it, a particle is to move at the constant velocity v = (3 m/s)i - (4 m/s)j. One of the forces is F1 = (2N)i + (-6N)j. What is the other force?


2. Relevant equations

Fnet = ma


3. The attempt at a solution

Well, I'm really just wanting a hint. I know that the acceleration is zero because the velocity is constant. So how do I use velocity to find the second force? Surely I'm missing something fundamental here. Once again, just a hint would be nice.
You pretty much gave yourself a hint when you said that there is no net force. Since one of the two forces are given, what's the other one?
 
You pretty much gave yourself a hint when you said that there is no net force. Since one of the two forces are given, what's the other one?

(-2N)i + (6N)j ?
 

PhanthomJay

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Gold Member
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429
Oh okay! Thanks!
 

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