Given a force equation and mass, find velocity

AI Thread Summary
To find the velocity of a particle given the force equation F = 9.0 + 2.0t - 4.0t² and mass 3.0 kg, the correct approach involves using Newton's second law, F = ma, to derive acceleration. Since acceleration is not constant, integral calculus is necessary to determine velocity over time. However, the discussion indicates that the participant is limited to derivational calculus for their class, which complicates the solution. The participant is uncertain about the correct motion equation to use, as substituting values led to an unexpected result of 0 m/s. Clarification on the application of calculus in this context is needed to properly derive the velocity equation.
gwhite00
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Homework Statement



The force on a particle of mass 3.0 kg moving in one dimension at time t, is given by:

F = 9.0 +2.0t - 4.0t2. What is the velocity of the particle? (Let v0=0 and ti=0)

Homework Equations


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I know to use F = ma for sure.

And I believe this is the motion equation I should be using, but I'm not completely sure: v = v0 + at

The Attempt at a Solution


[/B]
I substituted in the given equation for F and the given mass into Newton's 2nd Law equation and solved for the acceleration.

I then further substituted in acceleration into the velocity equation and let v0 = 0 and t = 0, which just appeared to make the velocity 0 m/s which doesn't seem correct.

Could someone point me in the correct direction?
 
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Hi gwhite00. I see you are new here. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

F= ma
can give you the acceleration vs time graph, then use integral calculus.

Acceleration is not constant.
 
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Thanks NascentOxygen for your quick reply.

While I do know how to use integral calculus being in Calculus III, we are not actually using it in our class. So far my professor has only touched on derivational calculus.

I know from previous problem sets written by this professor that his calculus based problems don't even up with a integer answer so I know that t will be part of my result.

I'm just not sure if I'm using the correct equation of motion to achieve an answer of a velocity equation at time t as an answer.
 
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