# Physics

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A 64 kg bicyclist rides his 7.7 kg bicycle with a speed of 13.5 m/s.

How much work must be done by the brakes to bring the bike and rider to a stop?

How far does the bicycle travel if it takes 4.5 s to come to rest?

What is the magnitude of the braking force?

I know the work in the first question is -6.43366 kJ but I have no idea how to find the distance and force.

• Physics -

average velocity= 13.5m/s * 1/2
distance= avgvelocity*time

force*distance= initial KE
solve for force.

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