can being hit by a car really cause your shoes to fly up in the air or is it just a myth?

It's much more likely that your feet would end up under the car, but in the event that you go over the hood, I would say that it's possible, but about as likely as your shoe flying off when you kick your foot, which happens all of the time.

Not really a myth as much as a preference on how tight you should tie your shoe. In my opinion, shoes have too large of a range of possible looseness for it to be practical to test.

i guess thats true but i thought it would be fun to see how they would test it

They would start with a simple swinging lead pipe with a shoe on the end of it, and by the end of the episode they would have worked up a robotic replica of the lower half of a human body to ram a car into.

Or so I theorize...