Q: An inclined plane at 30 degrees is 6.4m long. A book, which has a kinetic coefficient of friction with the incline of 0.2, is placed at the top and immediately begins to slide. Using energy considerations, how long will it take for the book to reach the bottom of the incline?(adsbygoogle = window.adsbygoogle || []).push({});

my solution is as follows:

6.4mg(sin(30))=0.5mv^2+0.2mg(cos(30))6.4

cancel out m and find v.

use vf^2=vi^2+2ad to find a

use d=vit+0.5at^2 to find t.

i think this solution works, but as you can see, it doesn't really "use energy considerations"...

any idea how i should go about solving this problem?

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# Homework Help: Power energy problem

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