hi,if it was welded rail,you would not hear them coming until they were right
on top of you,if you were lucky,thanks ken
--- On Sat, 11/14/09, smokyjoe66 <js08ws62@sbcglobal.net> wrote:
From: smokyjoe66 <js08ws62@sbcglobal.net>
Subject: [CBQ] Railroad Freight Cars Moving on Their Own
To: CBQ@yahoogroups.com
Date: Saturday, November 14, 2009, 10:47 PM
It seems to me that everyone on this list is here because we admire,
love, and are generally curious about all the aspects of railroading. So, this
question, though off-topic, might be of general interest to all, and of
specific interest to those who know physics.
Railroading began and continues to be a popular and effective way of moving
freight because a rolling steel wheel on a steel rail is very efficient. I have
seen reports that an 8- wheel freight car rests on less than 2 square inches.
And, it is steel on steel - little friction. Moreover, I am sure all of us
have witnessed the very long distances that a very slow moving freight car can
roll on its own. It is phenomenal. So… here's a theoretical question:
If an ordinary, empty, boxcar resting on 2 roller-bearing 4-wheel trucks was
given a 50 mile an hour push on a perfectly level, perfectly straight railroad
track on a windless day, how far would it go before stopping on its own?
It also would be interesting to hear some of your stories known from personal
experience regarding long distances rolled by railroad cars moving on their
own. Another phenomenon worthy of comment would be just how silently they roll.
I'm sure many have stories about that, too.
[Non-text portions of this message have been removed]
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