Question

A car is stopped at a red light. When the light turns green, the car accelerates until it reaches a final velocity of 45 m/s. It takes the car 12 s to reach this speed. How far does the car travel during this time.

Answer 1

Speed at the beginning  =  zero

Speed after 12 seconds  =  45 m/s

Average speed during the 12 seconds  =  (1/2) · (0 + 45)  =  22.5 m/s

Distance covered in 12 seconds at an average speed of 22.5 m/s  :

Distance = (speed) x (time)

Distance = (22.5 m/s) x (12 sec)

Distance   =  270 meters