A skateboard is more battery pack than chariot. The deck hums under a single push, wheels spinning up while the wooden plank bows by millimeters, hiding elastic potential energy in its fibers and rotational kinetic energy in the polyurethane cylinders that now look deceptively passive.
The common claim that wheels somehow pull the board forward misses the point, because once your foot leaves the ground every force along the direction of motion is either friction or inertia, with the bearings and contact patch only deciding how slowly that stored energy bleeds away as heat. Your kick injects linear momentum into your center of mass, yet it also twists the trucks and loads the deck, so part of the work shifts into bending and spinning instead of pure translation, a quiet accounting move that extends the glide while static friction at the top surface keeps your shoes locked to the moving platform.
More interesting than the ride is the bookkeeping. Each wobble, each tiny compression of bushings and deck, shuttles energy between translational motion and internal modes like flexural vibration, and that constant exchange lets the board shrug off small bumps without an immediate stop, even as rolling resistance and air drag drain the system. What looks like effortless coasting is really a negotiated truce between frictional losses, moment of inertia in the spinning wheels, and the springlike behavior of the deck, a compact lesson in classical mechanics hiding under scratched grip tape.