Originally Posted by
dynaryder
Wrong. I noticed a world of difference swapping tires on my bikes.
Yes. There was a difference
but you didn't understand the cause.
Huh? First,you just proved yourself wrong. You actually had to put effort into spinning that wheel up,while hitting the brake required almost none.Second,what does this have to do with riding the bike?
I'm sorry: I thought that experiment was idiot proof. But you seem to believe that the energy stored in two identical wheels spinning at the same RPM can be enormously different: I honestly thought this was too absurd to need addressing. Energy stored in the wheel is 0.5 x mass x radius x the square of spin rate; the energy stored
in the wheel is the same whether the bike is rolling down an alpine mountain with Lance The Liar onboard or upside down with a 12 year flicking the pedals around.
Which, to be honest, should have been explained in high school physics when you were about 12.
Second,what does this have to do with riding the bike? In that example,there's only the momentum of the wheel spinning,when riding the bike you have the weight of the bike+rider,plus gravity if going down hill to deal with.
What it does it that it shows that contribution of THE WHEEL MASS to the above is minuscule. Which is what we were discussing. The process you are struggling with is called "coherent logical argument"...