Hi there, I was wondering if anyone could help me with a centripetal motion question.(adsbygoogle = window.adsbygoogle || []).push({});

"A cyclist competes in a one-lap race around a flat, circular course of radiusr. Starting from rest and speeding up at a constant rate throughout the race, the cyclist covers the entire course in a timeΔt. The mass of the bicycle (including the rider) ism. What is the magnitude of the net forceFacting on the bicycle as it crosses the finish line?_{net}

FindF, the magnitude of the net force acting on the cyclist at the finish line._{net}

Express the net force in terms ofr,Δt,m, andπ."

My thinking was as follows:

In circular motion,F=_{net}F= mv_{centripetal}^{2}/Δt

I also know that v=2πr/Δt

Substituting the latter equation into the former, I get (m*4π^{2}r)/Δt^{2}

However, I am being told that my answer is "off by a multiplicative factor". I worked through a series of hints for this problem with a friend, only to come up with the same answer. Any help is appreciated!

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# Homework Help: Centripetal motion

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