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.
MEDIUMs = ((v_i + v_f)/2)t
Average Velocity and Constant Acceleration: FE Civil practice problem 1
For the Granite Crossing arterial overlay, a resident engineer preparing a permit comment response tracks equipment accelerating uniformly from 10 m/s to 22 m/s over 9 s. What distance is traveled?
- A84.4 m
- B164.3 m
- C144.0 m
- D183.5 m
Show the answer and worked solution
Answer: C — 144.0 m
Worked solution
- Step 1. Find average velocity
v_avg = (v_i + v_f)/2
v_avg = (10 + 22)/2 = 16 m/s
- Step 2. Multiply by time
s = v_avg t
s = 16(9) = 144 m
Why the other choices are wrong
- Choice A
- Nothing in the uniform-acceleration relationship supports this magnitude; the distance equals the mean of the initial and final speeds multiplied by the elapsed time, and this figure is not that product.
- Choice B
- This value cannot be reproduced from the average-velocity formula; multiplying the arithmetic mean of the two speeds by the given time interval, with no extra adjustment, yields a different distance than shown here.
- Choice D
- The mean of the initial and final speeds multiplied by the elapsed time does not reach this total; the distance follows only from that single average-velocity product computed once with the numbers given.