"Lewis Hartswick" wrote in message
...
I think I see another like my dad. He always said a rocket would not
work
in space since there was nothing to "push against". :-)
...lew...

I had the same argument with my high school physics teacher back in 1953. He
swore that rockets wouldn't work in the vacuum of space with nothing to push
against. I wasn't totally correct in my argument, I was arguing that the
main force driving the rocket
was the unbalanced high pressure in the rocket engine (zero force on the
open nozzle end and thousands of lbs force on the closed other end of the
engine). I was, I think, more correct than he was, though. I didn't know
enough then to even consider the ejection
velocity of the exhaust, etc.

Harold Burton