The initial speed of the car is 150 km/h. As the driver approaches a crossroad he realizes that he has to stop and applies his brakes at a point 50 m away from the point where he needs to stop. By doing so he is able to stop his car...

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The initial speed of the car is 150 km/h. As the driver approaches a crossroad he realizes that he has to stop and applies his brakes at a point 50 m away from the point where he needs to stop. By doing so he is able to stop his car in time.

To determine the resulting acceleration due to the application of the brakes use the formula `v^2 - u^2 = 2*a*s` where v is the final velocity, u is the initial velocity and a is the acceleration of the object over the distance s.

Here, v = 0, u = 150, s = 50/1000 km

`0 - 150^2 = 2*a*(50/1000)`

=> `a = -150^2*10`

=> `a = -225000`

The application of the brakes decreases the speed of the car at a rate 225000 km/h^2. The acceleration here is negative and equal to -225000 km/h^2