Motion of a Ball Rolled over a Shallow Step

A ball rolled over a shallow step will experience an increase in velocity along the direction perpendicular to the step. This causes a deflection in the ball’s trajectory. In this paper, we derive the equations that describe the motion of a ball rolled over a shallow step and present the results of our experimental test. This simple demonstration can be used in any classroom where the physics teacher has access to a ball and a stack of papers. Prior work has shown that a ball rolled over an edge can maintain its speed, as is commonly assumed, but it can also experience an increase or even decrease in speed.^1,2 The ball can either roll without slipping while it is in contact with the edge, or else begin to slip before it leaves the edge.³ In this paper, we will consider the case where the ball rolls without slipping...