1. The problem statement, all variables and given/known data There is a man walking on a disk with mass 70 kg and speed 4 m/s. He walks on a circle with radius 1,5 m. How fast does the disk (mass 200 kg and radius 2 m) under him rotates (need to calculate angular velocity) 2. Relevant equations angular momentum = J * w (J-moment of inertia, w, angular velocity) 3. The attempt at a solution (J_disk) * (w_disk) = (J_man) * (w_man) 1/2 MR^2 *(w_disk) = (mr^2* ( v_man)) / r (w_disk) = mr(v_man) / MR^2 (w_disk) =1,05 /s What am I doing wrong?