Answer:

Explanation:
The gravitational force between two corpses is given by the following equation:

Where F is the force, G is the gravitational constant
(
), M and m are the masses of the corpses and d is the distance between them.
So we have that:


Let say the two train cars are of masses
and 
now if the speed of two cars are
and 
then we can say that the momentum of two cars before they collide is given by

here two cars are moving in opposite direction so we can say that the net momentum is subtraction of two cars momentum.
Now since in these two car motion there is no external force on them while they collide
So the momentum of two cars are always conserved.
hence we can say that the final momentum of two cars will be same after collision as it is before collision

==> Jot down notes before and after making each call, and avoid calling during business hours when people are busy.
==> Save all emails and bills, and follow up to make sure people did what they said they would do.
Well the volcanos come from the lower crust and moves up with changes the climate
Answer:
if the object is not in motion
Explanation: