Physics

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The city is trying to figure out how long the traffic light should stay yellow at an intersection. The speed limit on the road is 45.0 km/h and the intersection is 23.0 m wide. A car is traveling at the speed limit in the positive direction and can brake with an acceleration of -5.20 m/s2. (a) If the car is to stop on the white line, before entering the intersection, what is the minimum distance from the line at which the driver must apply the brakes? (3sigfigs)

  • Physics -

    Vo = 45km/h = 45000m/3600s = 12.5 m/s.

    V^2 = Vo^2 + 2a*d.
    0 = (12.5)^2 - 2*5.2*d.
    d = ?.

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