Originally Posted By: paul

we can say that the collision is inelastic so when the two
collide they do not deform , the 100kg mass transfers its force to the earth.

That's not what 'inelastic' usually means. But if they really don't deform then the ball stops instantly. Stopping instantly applies an infinite force, which of course isn't possible. Perfectly undeformable bodies aren't possible either so it's OK.


Quote:

its the same mass and the same acceleration as in the example.

No. In the pipe the acceleration wasn't 40m/s^2. Just work through my calculations in bold in a recent message, I think that sums up my entire argument pretty clearly. Point to any specific lines you don't like.


I'm about to give up Paul. You used to be pretty competent with physics, but all your skills seem to have gone to the dogs with this tube thing, and getting progressively worse.