If the wheel isn't round, the axle would be forced to move up & down as the wheel turns, effectively creating a series of small uphills and downhills.
And if the uphill gets too steep, like with a perfect square,, the wheel might start to slide instead of turn, at which you lose the point of having wheels in the first place.
Wheels are round now and have always been round.
they are round
all of them are round
--G-c-ccc-e-g-e-c--- The wheels on the bus go round and round d-B-G---g-e-c- Round and round, round and round G-c-ccc-e-g-e-c--- The wheels on the bus go round and round d---G--Gc--- All through the town.
Wheels Go Round - 2014 was released on: USA: 1 December 2014 (limited)
Not deliberately. But historically, it was difficult to form perfectly round wheels.
Actually there are lots of vehicles which do not have round wheels. A sled has runners (runners are essentially large skis). A military tank runs on caterpillar treads. Various forms of air travel do not require wheels (although some do use landing wheels). Boats do not require wheels (although they may have steering wheels). And so forth. If you are asking why wheels are round instead of some other shape, round wheels roll more easily than any other shape.
the wheels go round and round up and down side to side very flexible easy to use
round wheels, probably metal. KV
Lots of cheeses are made into "wheels". It describes the large round shape they are made into.
The wheels on tHe bus go round and round
when you pedal, they go round?!?