Jason while driving on Kukum highway at 70 m.s – 1 seeing the traffic light turn red, he applies the brake and comes to rest in a time of 2 seconds. What is his deceleration?

Answer 1

You can use the following equation of motion: v = u + at

v is 0, since the vehicle comes to a stop.
u is given to be 70m/s
t is 2 seconds

Solve for a. You will get a negative value, which implies deceleration.