A car starts from rest and moves along the x-axis with constant acceleration 5 ms–2 for 8 seconds. If it then continues with constant velocity, what distance will the car cover in 12 seconds since it started from the rest?
The distance travelled in first 8 s, x1 = 0 + 1/2
(5)(8)2 =160 m
At this point the velocity v = u + at= 0 + (5�8) = 40 m s�1
Therefore, the distance covered in last four seconds, x2 =
(40�4) m = 160 m
Thus, the total distance x = x1 + x2 = + = (160 + 160) m = 320 m
