I‘m rolling a wooden toy car down a hill. What‘s the best kind of wheel to make it go fastest?A big or small wheel? Thin or fat? Heavy or light?
smaller, lighter wheels the larger and more massive the wheel, the more rotational inertia the car will have and the greater fraction of energy will go into rolling as opposed to going into translating, meaning motion down the hill if you are familiar with the concept of moment of inertia, the larger more massive wheels will have a greater moment of inertia, and their cars will have a slower straight ahead speed of course, there are other constraints.if the wheels are too light they might not support the weight of the car, so you can't have microscopically small wheels, but you want to keep them as small in radius and light as possible
