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Re: Steepest train/tram line
I wrote:
>I'm a little confused. Does the xx of 1 in xx represent the
horizontal
>distance or the distance traveled (length of rail used). In other
>words, if we imagined a certain steep hill as a 3:4:5 right triangle, 4
>being the horizontal distance, 3 being the vertical distance, and 5
>being the distance traveled, would it be called 1 in 1.66 (3 vertical
>in (5 distance/3 vertical)) or 1 in 1.33 (3 vertical in (4 horizontal/3
>vertical)) ?
...then James Robinson answered:
>It's based on horizontal distance. In your example, it would be 1 in
>1.33, or 75% for those prone to using that other system. It's done
this
>way as it is consistent with how the routes were surveyed. Surveys are
>mostly done using a horizontal plane as reference. In most railroad
>applications the difference is trivial.
...but Geoff Lambert answered:
>The former, strictly speaking. But the two distances are so close for
>all reasonable grades, that it doesn't really matter. See my earlier
>post regarding the equivalence of sin(theta), tan(theta) and theta.
..so now I still don't know! Is the grade of an office elevator (lift)
1 in 1 or 1 in 0?