Jiminy Jones was driving his Aston Martin last night with constant speed of 120 km/h. He suddenly saw a big tree on his way, 100 m away and hit the brake. His car stopped
right before the tree. Determine:
The acceleration of the car. The amount of time it took the car to stop, after he hit the brake.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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okay i have so many questions. but the big one here is: um wt..f is this mess? ?