Question

A car starts from rest and moves along a straight line with constant acceleration 5 ms–2
for 8
seconds. (2)
(a) Plot the velocity time graph from t = 0 to 8s.
(b) Find the distance covered in 8s.

Answer 1

Explanation:

Here, u=0,a=5m/s2,t=8s

From s=ut+12at2

s=0+12×5×82=160m

This is the distance moved by the car is first 8sec. Velocity at the end of 8s is

v=u+at=0+5×8=40m/s.

As this velocity is uniform, distance moved in next 4s

s'=v×t=40×4=160m

Total distance covered by the car in 12s

=s+s'=160+160=320m