Answer:
The car travels at twice the velocity of the truck.
Step-by-step explanation:
As we know that momentum is defined as the product of mass and velocity
so here we know
mass of the car = 900 kg
mass of the truck = 1800 kg
now let say that the speed of car =

speed of truck =

so if the momentum of car and truck is same


so we can say that car will move with double the speed of truck