Answer:



negative sign denotes deceleration.


Explanation:
Given:
- initial speed of blue car,

- initial speed of yellow car,

- acceleration rate of blue car,

- time for which the blue car accelerates,

- time for which the blue car moves with uniform speed before decelerating,

- total distance covered by the blue car before coming to rest,

- distance at which the the yellow car intercepts the blue car just as the blue car come to rest,

1)
<u>Speed of blue car after 2.6 seconds of starting the motion:</u>
Applying the equation of motion:



<u>Speed of blue car after 7.2 seconds of starting the motion:</u>
∵The car accelerates uniformly for 3.3 seconds after which its speed becomes uniform for the next 14.3 second before it applies the brake.
so,



<u>Distance travelled by the blue car before application of brakes:</u>
This distance will be
(distance travelled during the accelerated motion) + (distance travelled at uniform motion)
<em>Now the distance travelled during the accelerated motion:</em>



<em>Now the distance travelled at uniform motion:</em>


Finally:



<u>Acceleration of the blue car once the brakes are applied</u>
Here we have:
initial velocity, 
final velocity, 
distance covered while deceleration, 

Using the equation of motion:


negative sign denotes deceleration.
<u>The total time for which the blue car moves:</u>
........................(1)
<em>Now the time taken to stop the blue car after application of brakes:</em>
Using the eq. of motion:



Putting respective values in eq. (1)


<u>For the acceleration of the yellow car:</u>
We apply the law of motion:

<em>Here the time taken by the yellow car is same for the same distance as it intercepts just before the stopping of blue car.</em>
Now,

