(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A cyclist intends to cycle up a 14-degree inclined hill whose vertical height is 120 m. Assuming the mass of bicycle plus person is 75 kg

a) Calculate how much work is done against gravity

b) A complete revolution of the pedals moves the bike 5.10 m along its path. Calculate the average force that must be exerted on the pedals tangent to their circular path. Neglect work done by friction and other losses. The pedals turn in a circle of diameter 36 cm.

2. Relevant equations

I assume work-energy theorem... and maybe centripetal acceleration/force formulae

(W_net=1/2*m*v_2^2-1/2*m*v_1^2)

(a_c=v^2/r)

3. The attempt at a solution

The first part wasn't too bad: I got 88200 J.

Second part; I tried using a_tangential = Δv/Δt, but I can't get the time. I'm not sure how to use the radius and the fact that each revolution brings bike 5.10 m forward; I suspect centripetal acceleration formula is somehow involved.

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# Homework Help: Force on pedals; cyclist up incline

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