Calculating Work Done by a Confusing Force Function | F=ma, W=Fd

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DrummingAtom
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Homework Statement


The force on a particle is directed along an x-axis and given by [tex]F = F_0(\frac {x}{x_0} -1)[/tex]. Find the work done by the force in moving the particle from x = 0 to [tex]x = 2x_0[/tex]


Homework Equations


F=ma, W=Fd, etc.


The Attempt at a Solution


I don't even know how to interpret that function. Does the [tex]x_0[/tex] mean the initial position? Does [tex]F_0[/tex] mean the initial force? I'm so confused. Any help would be appreciated.
 
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Hi DrummingAtom! :smile:

(try using the X2 tag just above the Reply box :wink:)
DrummingAtom said:
I don't even know how to interpret that function. Does the [tex]x_0[/tex] mean the initial position? Does [tex]F_0[/tex] mean the initial force?

That's right :smile:

a "0" subscript always means a constant (usually the value at t = 0). :wink:

(oh … except in relativity, where x0 means time! :rolleyes: :biggrin:)
 
I'm still confused on this one. So, if x0 F0 are constants then how would the graph of this function look? Because they want you to graph F(x) before integrating. I mean what do you pick for your constant in a situation like this? I know it's going to be a linear function.
 
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DrummingAtom said:
I'm still confused on this one. So, if x0 F0 are constants then how would the graph of this function look? Because they want you to graph F(x) before integrating. I mean what do you pick for your constant in a situation like this? I know it's going to be a linear function.

It doesn't really matter, as long as x0 is not 0 (otherwise you'll have a divide by zero problem). But if you want to make your life easier, put it on the positive x-axis somewhere. I suggest putting it at x = 1. That way you'll integrate from 0 to 2. But don't label you x-axis with '1' and '2'; rather label you x-axis to go from

0...x0...2x0...3x0...

Now when you consider your graph's labels, you are integrating from 0 to 2x0, as the problem specifies! :cool:

The y-axis is F. So where does F0 fit into your graph? I'll let you do that.
 
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