Waiting station, La Posada porch
BNSF arrival
FinishedToday’s science lesson. (mllg)
Is it Newton’s first law or second? An object in motion tends to stay in motion, an object at rest tends to stay at rest. Whichever law, Warren Buffet’s BNSF demonstrates its effect every time one of its 80-100 car trains pulled by 4 colossal orange engines stops and starts on one of the 5 or 6 tracks in front of the La Posada hotel.
Those engines are powerful, but even 4 cannot start a 80 car train that is standing still, it can pull them while in motion, but Newton’s first law prevents them from starting en masse. So, train couplings are designed so there is a 2 or 3 inch gap in each one, this way the engine is only pulling 1 car at a time, until it is in motion, and then pulls on the second.
Most start ups seem to occur by the train first backing up, so that the gap between couplings is at its maximum, then slowly pulling ahead. You can hear each coupling engage is a series of thuds as the forward motion begins.
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