Answer:
4 hours
Step-by-step explanation:
Both cars here travel with uniform motion (constant velocity), so the relationship between distance covered, time taken and speed is:
[tex]t=\frac{d}{v}[/tex]
where
t is the time taken
d is the distance covered
v is the speed of the car
Here we have:
[tex]v_1 = 120 km/h[/tex] (speed of the 1st car)
[tex]v_2=80 km/h[/tex] (speed of the 2nd car)
d = 960 km is the total distance covered by each car
So for car 1, the time taken is:
[tex]t_1=\frac{960}{120}=8 h[/tex]
While for car 2, the time taken is:
[tex]t_2=\frac{960}{80}=12 h[/tex]
And so, the difference in arrival time between the two cars is:
[tex]\Delta t =t_2-t_1 =12 -8 = 4 h[/tex]