Question

A car with a mass of 1800 kg is initially travelling with a velocity of 22 m/s [N] when it collides with a truck with a mass of 3200 kg traveling with a velocity of 14 m/s [E]. If the two vehicles become attached during the collision, determine their final velocity.

Answer 1

north momentum before = 1800*22
east momentum before = 3200*14

north momentum after = 5000 Vn
east momentum after = 5000 Ve

so
Vn = 1800*22/5000
Ve = 3200*14/5000

v = sqrt (Vn^2 + Ve^2)
tan angle east of north (compass heading)
= Ve/Vn

Answer 2

I still don't understand.