Hi folks:(adsbygoogle = window.adsbygoogle || []).push({});

Question for you guys. I've generalized a question that keeps coming up in class...but that keeps going unexplained. This is a somewhat involved problem which requires integrating force to find work. Thing is, force is always integrated as a function of position NOT time. This type of problem keeps throwing me for a loop because you end up finding a force equation that's basically F(t)...and end up having to integrate it in terms of dx to find work. I know I'm missing something here, but I can't figure out what. It's stage B where things start getting tricky.

Here's the challenge problem of the day then...

Imagine you have a rabbit of mass M whose position is given as a function of time is given by x = (3t - 4t^2 + t^3)i, where x is in meters and t is in seconds.

(A) What is the acceleration of the rabbit for any time t?

(B) What is the work done by the rabbit for the first five seconds of its journey?

(C) What is the power of the rabbit at t = 3.0 seconds?

(D) What is the average power of the rabbit during the first five seconds of its journey?

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# Homework Help: Integrating Work from Force(time)

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