This is not a silly question as no one else has answered it correctly. There used to be a difference between rims and wheels on cars, but no longer, There are still seperate rims and wheels on large trucks.
A wheel is the rotating part which bolts to the axle. The rim, if seperate, is the part which holds the rubber tire. On wooden wheeels the rim was metal, the wheel was wooden spokes. A spare tire would be mounted on a rim, filled with air. But the car only had four wheels. The rim and wheel bolted together in a circle about where the valve stem is today.
Bill D.
Ps Locomotives use seperate wheels and tires even today. But the tires are steel.
