释义 |
Railroad Track ProblemGiven a straight segment of track of length , add a small segment so that the track bows into a circular Arc. Find the maximum displacement of the bowed track. The Pythagorean Theorem gives
 | (1) |
But is simply , so
 | (2) |
Solving (1) and (2) for gives
 | (3) |
Expressing the length of the Arc in terms of the central angle,
But is given by
 | (5) |
so plugging in gives
 | (6) |
 | (7) |
For ,
 | (8) |
Therefore,
Keeping only terms to order ,
 | (10) |
 | (11) |
so
 | (12) |
and
 | (13) |
If we take and 1 foot, then feet. |