Originally Posted By: paul
in the above what do you think the product is?

It means mass x velocity


Quote:
kallog the sum of magnatudes is the total momentum.


We don't need to go any further until you work this out. Otherwise it's a waste of time.

pMass = -1
pPipe = 1

"the sum of the magnitudes of the momentums" = |-1| + |1| = 2
"the sum of the momentums" = -1 + 1 = 0

Both are correct, but only one is conserved.