Kinetic Trajectory Test

I marched down the driveway to survey the neighborhood street curb. Wedged tight between the concrete gutter and the asphalt was a dense rubber bounce ball. I decided to evaluate its kinetic properties. Bracing my boots on the curb bevel, I drove the green wedge of my left arm beneath the sphere and levered it upward with a single thrust. The ball popped free, hit the asphalt with a sharp snap, and bounced along the gutter line toward a cast-iron drain. I tracked its arc and tapped it with my right foot to measure rolling friction. Elastic rebound is remarkably efficient.