A friction cart with a fan attached (total mass = 349 g) moves along a track with a fan unit exerting a force of 2.21 N on it. If the coeeficients of kinetic and rolling friction between the cart and the track are μk=0.29 and μr=0.04 respectively, what is its acceleration? (Hint: The cart is affected by both kinetic and rolling friciton at the same time.)

Question

photon336 · Answer

I guess for this we have our box and the fan attached to it. when we apply a force to it the force of friction will oppose the motion. we draw out all the forces. the normal force is perpendicular to the surface. the force of gravity of both of those objects. we choose our coordinate system. up is positive down is negative. and in the direction of our motion is positive, the opposite negative 

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coordinate system

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