Question

A car starts from rest and moves along the x-axis with constant acceleration 5 m s–2 for 8 seconds. If it then continues with constant velocity, what distances will the car cover in 12 seconds since it started from the rest?

Answer 1

Answer:

320m

Explanation:

To calculate distance traveled in first 8s

we have to use kinematics equation.

It is given that body starts from rest means u=0

Therefore,

S1=ut+(1/2)at2

S1 =0+(1/2)×5×64

 S1 =160 m.

The velocity attained in 8 seconds is given by formula,

v=u+at

v=0+5×8=40 m/s.

The distance traveled in the next 4 seconds will be,

S=speed×time

S2=40×4=160 m.

So, the total distance traveled by car is

S1 + S2=160+160

S1 + S2 = 320m

Answer 2

Answer:

320 m

Explanation:

It is the right answer