A car was traveling at 45 m/s toward a traffic signal when the light suddenly changed from green to red. The driver slams on the brakes, stopping the car in 3.3 seconds. a. What is the acceleration of the car? b. How far did the car travel before it came to a stop

Acceleration =13.63m/s^2

initial velocity = v = 45

final velocity = u = 0

acceleration = v-u/t

6,000,000 J (6 million)

Explanation:

Refer to the equations for potential and kinetic energy.

Because the automobile is on the ground (it does not give a height above the ground, therefore we can assume that it is on the ground), height = 0.  If you plug in 0 for h in the potential energy equation, we get PE = 0 J.

Therefore, all of the energy is kinetic.  Plug in the given information into the kinetic energy equation.  M = 1200 kg and v = 100 m/s