A truck is stopped at a stoplight. When the light turns green, it accelerates at 2.9 m/s2. At the same instant, a car passes the truck going 12 m/s. Where and when does the truck catch up with the car?

Answer 1

The distance S travelled by an object moving at an initial speed v m/s and accelerating at the rate of a m/s² over a period of t sec. is given by
S(t) = ut+(1/2)at²

For the truck:
u=12 m/s
a=0

For the car,
u=0,
a=2.9 m/s²

Equate the distances travelled by the car and the truck, then solve for t (when).
Substitute t into one of the equations to get S (where).