Original question written by FE Exam AI Prep from the public FE Civil exam specification. Before release, a solver model re-derived the answer twice from the question alone, without its answer key, and a critic model checked the result, and the arithmetic was re-run as an executable calculation. No licensed engineer reviews these questions. It is not an NCEES question and does not come from any NCEES practice exam. FE Exam AI Prep is an independent study tool and is not affiliated with, endorsed by, or sponsored by NCEES.
Traffic Flow, Speed and Density: FE Civil practice problem 6
For the North Channel school frontage improvement, a transportation analyst preparing a resident-engineer calculation check uses the traffic stream relation with speed 65 mph and density 24 veh/mi. What flow rate is indicated?
- A1779 veh/hr
- B1560 veh/hr
- C1893 veh/hr
- D2410 veh/hr
Show the answer and worked solution
Answer: B — 1560 veh/hr
Worked solution
- Step 1. Use traffic flow relation
q = k v
q = 24(65) = 1560 veh/hr
Why the other choices are wrong
- Choice A
- This figure is about forty-five percent higher than the straight density-times-speed product, a gap too large to trace to one ordinary miscalculation. Multiplying k by v directly and nothing more yields the verified flow rate of 1560 veh/hr.
- Choice C
- This figure exceeds the straight density-times-speed product by roughly eighteen percent, an offset too irregular to trace to one obvious miscalculation. Multiplying k by v directly and nothing more yields the verified flow rate of 1560 veh/hr.
- Choice D
- This figure comes in about twenty-two percent under the straight density-times-speed product, a gap too irregular to trace to a single obvious miscalculation. Multiplying k by v directly, with nothing subtracted or scaled down, gives the verified flow rate of 1560 veh/hr.