Incline Calibration

I positioned a wooden ruler across a stack of three cork coasters on the dining table to form an inclined plane. At the summit, I held a smooth plastic button in place with my thumb, then released my grip. The button accelerated cleanly down the wood grain, gliding off the bevel and sliding across the table surface before coming to a stop. Stacking a fourth coaster made the gradient too steep, flipping the disc mid-transit. Three coasters yielded the optimal descent trajectory.