Answer:
[tex]2.8\; {\rm s}[/tex].
Explanation:
The velocity of vehicle [tex]2[/tex] relative to vehicle [tex]1[/tex] is:
[tex]\begin{aligned}& \text{velocity of 2 relative to 1} \\ =\; & (\text{velocity of 2 relative to ground}) \\ &- (\text{velocity of 1 relative to ground}) \\ =\; & 33\; {\rm m\cdot s^{-1} - 28\; {\rm m\cdot s^{-1}} \\ =\; & 5\; {\rm m\cdot s^{-1}} && (\text{to the east})\end{aligned}[/tex].
The displacement of vehicle [tex]2[/tex] relative to vehicle [tex]1[/tex] is currently [tex]0\; {\rm m}[/tex]. The rate at which this displacement increases is equal to the velocity of vehicle [tex]2\![/tex] relative to vehicle [tex]1\![/tex], which is [tex]5\; {\rm m\cdot s^{-1}}[/tex].
Thus, it would take [tex](14 \; {\rm m}) / (5\; {\rm m\cdot s^{-1}}) = 2.8\; {\rm s}[/tex] for this displacement to reach [tex]14\; {\rm m}[/tex].
