Answer:
The momentum would be doubled
Explanation:
The magnitude of the momentum of the freight train is given by:
[tex]p=mv[/tex]
where
m is the mass of the train
v is its speed
In this problem, we have that the speed of the train is unchanged, while the mass of the train is doubled:
[tex]m'=2m[/tex]
therefore, the new momentum is
[tex]p'=m'v=(2m)v=2(mv)=2p[/tex]
so, the momentum has also doubled.
