Answer:
a) [tex]v_{A_{B}}[/tex] = -30 m/s
b) [tex]v_{B_{A}}[/tex] = 30 m/s
Explanation:
a)
Consider the car A travel at a velocity of [tex]v_{A}[/tex] = 90 km/h and the car B travel at the velocity of [tex]v_{B}[/tex] = 120 km/h. As the velocity of the car B is greater than the car A, So it cross the car A. Consider The velocity of car A relative to car B is [tex]v_{A_{B}}[/tex] and it is equal to the velocity of car A minus the velocity of car B.
[tex]v_{A_{B}}[/tex] = [tex]v_{A}[/tex] - [tex]v_{B}[/tex]
[tex]v_{A_{B}}[/tex] = 90 - 120
[tex]v_{A_{B}}[/tex] = -30 m/s
b)
Consider The velocity of car B relative to car A is [tex]v_{B_{A}}[/tex] and it is equal to the velocity of car B minus the velocity of car A.
[tex]v_{B_{A}}[/tex] = [tex]v_{B}[/tex] - [tex]v_{A}[/tex]
[tex]v_{B_{A}}[/tex] = 120 - 90
[tex]v_{B_{A}}[/tex] = 30 m/s
