Electric potential energy and displacement

AI Thread Summary
The discussion revolves around calculating the work done by a time-varying force on a 5 kg mass with a displacement function of x = 5t - 8t². Participants note that while no specific force is provided, it can be derived from the displacement function by determining velocity and acceleration. The work done can be calculated using the line integral of the force or as the time integral of power, P = F*v, over the specified time interval from t = 0 to t = 5 seconds. The importance of understanding the relationship between force, mass, and acceleration in this context is emphasized. Overall, the conversation highlights the need for clarity on how to approach problems involving time-varying forces and displacement.
prolong199
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could someone please lead me in the right direction with this question. I am confused about the time varying force in determining the work done

A time-varying force acts on a 5 kg mass yielding a displacement
x = 5t - 8t2 (x in m). The work done by the force between the times
t = 0 and t = 5s, is

thanks.
 
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You're missing a bit of information here; are you sure you're given nothing about the force?
 
thats what I am thinking, it says a time varying force, but you can work out the force with regard to mass and acceleration fro the displacement function. So to answer your question, there is no other information provided for the question.
 
prolong199 said:
thats what I am thinking, it says a time varying force, but you can work out the force with regard to mass and acceleration fro the displacement function. So to answer your question, there is no other information provided for the question.

You are right, you can get both velocity and acceleration so the force too, from x(t). The work between two points is the line integral of the force, but it can be calculated as the time integral of the power P=F*v in the given time interval.

ehild
 
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