Alever is placed on a fulcrum. a rock is placed on the left end of the lever and a downward (clockwise) force is applied to the right end of the lever. what measurements would be most effective to you determine the angular momentum of the system? (assume the lever itself has negligible mass.) the angular velocity and mass of the rock and the radius of the lever the velocity of the force, the radius of the lever, and the mass of the rock the angular velocity and mass of the rock the mass of the rock, the length of the lever on both sides of the fulcrum, and the force applied on the right side of the lever