A truck is stopped at a stoplight. When the light turns green, the truck accelerates at 2.5 m/s squared. At the same instant, a car passes the truck going 15 m/s. Where and when does the truck catch up with the car?

2 answers

truck distance = (1/2)2.5 t^2
car distance = 15 t
so
15 t = 1.25 t^2
1.25 t^2 - 15 t = 0
t (1.25 t - 15) = 0
t = 0 of course or t = 15/1.25 = 12 seconds

distance = 15 * 12 = 180 meters
A 913 kg car is stopped at a traffic light. When the light turns green the car accelerates down the road due to the push from the engine and the friction from the road producing a net force of 2,306 N. How much acceleration does the car experience as it speeds up?