The correct option is C 600 m
Let a1 and a2 be the accelerations of truck and the car respectively.
Let d be the distance travelled by the truck before it gets side by side to the car
Therefore, distance travelled by the car before it gets side by side to the truck =d+150
Using second equation of motion for truck, we get
d=u1t+12a1t2
As the truck starts from rest
⇒u1=0
⇒d=12×1.5×t2 .....(i)
Using second equation of motion for car, we get
d+150=u2t+12a2t2
As the car also starts from rest
⇒u2=0
⇒d+150=12×2×t2 .....(ii)
On solving (i) and (ii), we get
t2=600 s2,d=450 m
∴ Distance travelled by the car to get side by side to the truck =d+150=600 m