Thank you, I like the explanation of the traffic flow, but I am a bit confused why we don't just do the spacing over the headway to find the velocity ( S= 250'/3s*3600s/1hr*1mile/5280ft=56.82mph)? I haven't taken a transportation class so I am not familiar with the terminology and I guess with hard questions involving jams and other variety that we need to convert it to density.
Hi Lea! When I think about it, you actually can do that. As you presented, we would still get the same answer. I believe my goal in this video was to relate the major variables of flow, density, and speed to each other. Should have honestly included you point at the end of the video! Well done.
250ft/5280ft = 0.0473485 Miles 3sec/60sec/60min = .000833hrs So .0473485miles/.000833hr is 56.8mph The exam is all about speed, if you can calculate the problem with basic math equations don’t waste time looking for the magic equation. This is as simple as converting units and dividing distance/time. 1-2 min solution.
Totally agree. Timing is crucial for this exam. In fact, you’ll likely not even write much at all inside that laminated booklet. Your approach is best 👍
![Speed / Density / Flow Relationships | NCEES Civil Engineering PE Exam [Section 5.1.1.4; 5.1.2]](http://i.ytimg.com/vi/DmrmtYLabrI/mqdefault.jpg)
Thank you, I like the explanation of the traffic flow, but I am a bit confused why we don't just do the spacing over the headway to find the velocity ( S= 250'/3s*3600s/1hr*1mile/5280ft=56.82mph)? I haven't taken a transportation class so I am not familiar with the terminology and I guess with hard questions involving jams and other variety that we need to convert it to density.
Hi Lea! When I think about it, you actually can do that. As you presented, we would still get the same answer. I believe my goal in this video was to relate the major variables of flow, density, and speed to each other.
Should have honestly included you point at the end of the video! Well done.
250ft/5280ft = 0.0473485 Miles
3sec/60sec/60min = .000833hrs
So .0473485miles/.000833hr is 56.8mph
The exam is all about speed, if you can calculate the problem with basic math equations don’t waste time looking for the magic equation. This is as simple as converting units and dividing distance/time. 1-2 min solution.
Totally agree. Timing is crucial for this exam. In fact, you’ll likely not even write much at all inside that laminated booklet.
Your approach is best 👍
Thank you! Nice explanation, keep it up!
Thank you!
Thank you
You’re welcome! Keep up the good work 💪🏼