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Determine the stopping distances for a car with an initial speed of 95 km/h and human reaction time of 1.0 s for the following accelerations.

1 Answer

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During the reaction time, the car has travelled,
95 km/hr * 1000 m/km * 1 hr/3600 sec * 1 sec = 26.39 meters
After the reaction time, the working formula is
Vf^2 - Vo^2 = 2ax
where
Vf = final velocity = 0 (when the car stops) Vo = initial velocity = 95 km/hr (given) = 26.39 m/sec. a = acceleration = -8 m/sec^2 (given) x = stopping distance after the reaction
Substituting,
0 - 26.39^2 = 2(-8)(s)
Solving for s,
s = 43.52 meters
Therefore, total distance traveled before car comes to a stop is
26.39 + 43.52 = 69.91 meters
User Kuti
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