I've watched/listened to that video several times, and for those who just skimmed past the link and haven't bothered, seriously, grab some headphones
and give it a whirl,
originally posted by: NicSign
Why doesn't the rocket enter space? Oh because it can't lol
That video brings profound ignorance to a whole new level. It wastes a alot of time talking about things that don't
apply, and never does talk about what does apply, the simple but important concept of "conservation of momentum", explained here:
Momentum Rocket Propulsion
If you ever fired a gun larger than a .22 you will have felt some recoil (there is some with .22 also but not much).
Before you fire the momentum of the system is zero, the gun and the bullet are not moving.
Conservation of momentum says after you fire the gun, momentum must be conserved, so total momentum of the gun/bullet/expanding gas system must still
be zero, so if the bullet is going one way, the gun must move the other way in order for total momentum to add to zero. That's essentially the idea of
how a rocket works in space, except the linked video uses the example of throwing a wrench instead of firing a gun, before talking about how the same
applies to rockets.
The other thing that is funny about that video is that it's saying it's a NASA conspiracy, but this thread isn't about a NASA rocket, it's about a
SpaceX rocket, so the whole idea of "NASA lies about their rockets" seems especially out of place in a thread about someone besides NASA showing that
they don't have to accept anything NASA says. SpaceX can make their own rocket and it works since they have people that understand simple things like
conservation of momentum.
firing a gun, yes there is recoil because pressure builds up between the gun and bullet. The pressure pushes the bullet out and in turn pushes the
gun. A rocket is like a gun firing a blank. The powder burns and moves out of the barrel only pushing off the air (assuming the gun powder was not
encased in anything).
Thrust equation is false because the PRESUMPTION that there is an equal and opposite force from gas movement due to pressure gradient force is
incorrect.