Answer
a)286m
b)40m/s
Work Step by Step
a) Let +x be in the direction of the motion of the vehicles.
We know the truck travels at a constant speed for a period of time t
We proceed to use $s-s_{0}=ut+\frac{1}{2}at^{2}$
$s_{truck}=20(t)$
For the car to overtake after the time t, they must travel the same distance at time t,
$s_{car}=0t+\frac{1}{2}(2.8)t^{2} = 20t $
Solving for t we get,
t=14.29s
Hence, $s$=20(14.29)=286m
b)To find velocity of the car, we proceed to use $v=u+at$
$v$=0+(2.8)(14.29)=40m/s
