A 65kg bicyclist rides his 8.8kg bicycle with a speed of 14m/s. (a) How much work must be done by the brakes to bring the bike and rider to a stop? (b) How far does the bicycle travel if it takes 4.0s to come to rest? (c) What is the magnitude of the braking force?(adsbygoogle = window.adsbygoogle || []).push({});

So for part (a) the equation I would use is W=1/2mv_f^2 - 1/2mv_i^2 correct? Which then I get for an answer is 7232.4=W which means 7232.4 Newtons?

For part (b) I know the work that it takes to stop the bicyclist and bicycle but what I'm confused on what equation I would need to use to figure that out.

thanks

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# Homework Help: Kinetic Energy and Work Energy Theorem

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