1. The problem statement, all variables and given/known data Side by side on the top of an incline plan with height=2 meters a cylinder (Ic= MR^2/2) and a sphere (Ie=2MR^2/5) with equal radius, that come down to the base, rolling without slipping. Mass of the cylinder = 2.0 kg; Mass of a sphere=4.0 kg. 2. Relevant equations $$K_r= 1/2 I \omega ^2$$ For rolling without slipping $$v=\omega R$$ 3. The attempt at a solution At first I thought this was a pretty linear problem. Applying both equations to both the sphere and the cylinder: $$K= 1/4 M_c v_c^2$$ $$K= 1/5 M_e v_e^2$$ Than I applied conservation of mechanical energy to determine velocity. However this is not correct since we don't know if there is a friction force (in fact we find out in the next question that it has). So how should I proceed in this case to determine the velocities? Thanks!