As a city planner, you receive complaints from local residentsabout the safety of nearby roads and streets. One complaintconcerns a stop sign at the corner of Pine Street and 1st Street.Residents complain that the speed limit in the area (55 mph) is toohigh to allow vehicles to stop in time. Under normal conditionsthis is not a problem, but when fog rolls in visibility can reduceto only 155 ft. Since fog is a common occurrence in this region,you decide to investigate. The state highway department states thatthe effective coefficient of friction between a rolling wheel andasphalt ranges between 0.842 and 0.941, whereas the effectivecoefficient of friction between a skidding (locked) wheel andasphalt ranges between 0.550 and 0.754. Vehicles of all typestravel on the road, from small VW bugs weighing 1370 lb to largetrucks weighing 8040 lb. Considering that some drivers will brakeproperly when slowing down and others will skid to stop, calculatethe minimum and maximum braking distance needed to ensure that allvehicles traveling at the posted speed limit can stop beforereaching the intersection.
minimum braking distance: ?ft
maximum braking distance: ?ft
Given that the goal is to allow all vehicles to come safely to astop before reaching the intersection, calculate the maximumdesired speed limit. maximum speed limit: ? mph
Which factors affect the soundness of your decision? (can bemultiple ones)
Reaction time of the drivers is not taken into account.
Newton's second law does not apply to this situation.
Drivers cannot be expected to obey the posted speed limit.
Precipitation from the fog can lower the coefficients offriction.