Traffic on a three-lane freeway observes a triangular flow-density relationship with free-flow speed vf=100km/h, capacity c=2000veh/h/lane,...

Traffic on a three-lane freeway observes a triangular flow-density relationship with free-flow speed vf=100km/h, capacity c=2000veh/h/lane, jam density kj=150veh/km/lane. Flow in the freeway from upstream is 5000veh/h, while the ramp flow is negligible (almost zero).At 9:45am, an accident occurs at point A. The vehicles involved close one lane of traffic (total capacity reduces to 4000veh/h) for 15min and afterwards the scene is clear (capacity returns to 6000veh/h). Lucy enters the freeway via the ramp at point B at 10:00am. Distance AB is equal to 6.5km.What time [h] does Lucy leave the queue?What time [h] does Lucy pass the accident scene (point A)?

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Ally Wells answered 4 months ago

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