Question

At the instant the traffic light turns green, a car that has been waiting at an intersection starts with a constant acceleration of 6 feet per second per second. At the same instant, a truck traveling with a constant velocity of 36 feet per second passes the car. (a) How far beyond its starting point will the car pass the truck?

Answer 1

d = 432 ft

Step-by-step explanation:

Let say after time "t" the car will overtake the truck

so at this position the distance moved by car and truck will be same

so we will have

`d_(car) = vt + (1)/(2)at^2`

`d_(car) = 0 + (1)/(2)(6)t^2`

`d_(car) = 3 t^2`

now the distance moved by the truck in the same time is given as

`d_(truck) = vt`

`d_(truck) = 36 t`

so we have

`3 t^2 = 36 t`

`t = 12 s`

so the distance move by the truck will be given as

`d = 36* 12`

`d = 432 ft`