While traversing a two-lane highway, the driver observes a girl, 60 m ahead, at the edge of the traveled way of the opposite direction about to cross the road. The lane width of the traveled way is 3.5 m. The vehicle is 2 m wide and 3 m long. The speed of the vehicle is 75 kph and the walking speed of the girl is 1.5 m/s. The vehicle is traveling along the centerline of the traveled way. Asssume that the driver's PR time is 0.8 sec and the coefficient of friction between the vehicle tires and the pavement is 0.4. a. If the roadway is level, will the girl be able to corss the road safely? b. If the roadway has down grade of 0.5%, what is the coefficient of friction between the tires and the pavement required so that the driver won't hit the girl? c. Using the original coefficient of friction between vehicle tires and the pavement, at what roadway grade is the vehicle traversing such that the vehicle was just able to stop without hitting the girl?

While traversing a two-lane highway, the driver observes a girl, 60 m ahead, at the edge of the traveled way of the opposite direction about to cross the road. The lane width of the traveled way is 3.5 m. The vehicle is 2 m wide and 3 m long. The speed of the vehicle is 75 kph and the walking speed of the girl is 1.5 m/s. The vehicle is traveling along the centerline of the traveled way. Asssume that the driver's PR time is 0.8 sec and the coefficient of friction between the vehicle tires and the pavement is 0.4. a. If the roadway is level, will the girl be able to corss the road safely? b. If the roadway has down grade of 0.5%, what is the coefficient of friction between the tires and the pavement required so that the driver won't hit the girl? c. Using the original coefficient of friction between vehicle tires and the pavement, at what roadway grade is the vehicle traversing such that the vehicle was just able to stop without hitting the girl?