"A box slides down a 30.0 degree ramp with an aceleration of 1.20m/s^2. Determine the coefficient of kinetic friction between the box and the ramp."(adsbygoogle = window.adsbygoogle || []).push({});

I know that the coefficient of kinetic friction is found by kinetic friction / normal force, but the only problems I've delt with in the past gave you the mass of the object. In those cases, I would find the force of gravity then use it to find the force upwards using the sin of the angle of the incline. From there, I would find the normal force subtracting force upwards from the force of gravity - then finally multiplying the mass times the acceleration to find the kinetic friction.

I know how to work through it one way, but I can't figure out how to work backwards given the acceleration and no mass. Could someone please point me in the right direction?

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# Homework Help: Help finding coefficient of kinetic friction

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