from what I can tell.

the pipe has force of 8000N
and a momentum of +4000Ns

the mass has no force
and a momentum of -4000Ns

so what will happen when the two collide is their momentums
cancel each other out.

and the pipe continues with a force of 8000N

but your welcome to pick some more straws , and I know you will.






3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.