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Could a heavy object cause a train derailment?
Duke C.

Posted on 05/16/2015 3:52:39 PM PDT by Duke C.

Basic physics states that F+MV² ( force= mass times velocity squared)
Let's say a thug tosses a bowling ball at Amtrak 188, presently moving at 70 MPH.
That would be 15LBS times 88FPS which would equal 1,742,000 foot pounds of energy.

Don't know if this is right, my physics is rusty. Anybody?


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To: EEGator

Yup. KE=1/2M(Vsquared)


21 posted on 05/16/2015 4:14:58 PM PDT by Chainmail (A simple rule of life: if you can be blamed, you're responsible.)
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To: Talisker
According to wiki the individual axle rating on an amtrak locomotive is 72,000 lbs., and I think it's safe to assume that the loco windshields have bulletproofing.

So neither the windshield nor the bowling ball would shatter, but bounce off after causing considerable damage to the windshield.
Just playing devil's advocate.
22 posted on 05/16/2015 4:15:46 PM PDT by Duke C.
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To: Duke C.

You better go relearn some basic physics. F does not equal MV-squared.


23 posted on 05/16/2015 4:16:38 PM PDT by MIchaelTArchangel
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To: Talisker

Train physics, Its all about the go-mentum.


24 posted on 05/16/2015 4:17:01 PM PDT by cripplecreek ("For by wise guidance you can wage your war")
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To: 9thLife

“Why do you want to square v?”

kinetic energy

E = (mv**2)/2

70 mph is just over 102 ft/sec, not 88 ft/sec

bowling ball mass of 15 pounds equates to 0.466 slugs (pounds are a unit of force, not mass)

gives us about 2425 foot-pounds of energy. So the analogy of a BB hitting an auto is not too far off.

Much about a collision result depends on the materials of the colliding objects, their angle of impact, their shape, etc. Momentum is a factor: the scalar product of mass and velocity.

To carry on with the analogy, a human struck by that 15-pound bowling ball traveling 70 mph (102 ft/sec) will sustain injuries quite different from a human struck by - say - a 30 cal bullet traveling 2700 ft/sec (common impact velocity fired from many hunting rifles), though the kinetic energy of the projectiles are nearly identical.


25 posted on 05/16/2015 4:19:47 PM PDT by schurmann
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To: tennmountainman; Duke C.

>> going 106 MPH into a 50 MPH curve.

Then he slammed on the brakes.


26 posted on 05/16/2015 4:21:41 PM PDT by george76 (Ward Churchill : Fake Indian, Fake Scholarship, and Fake Art)
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To: Duke C.

There is no debate. 106 MPH says it all. A train runs on a track. It’s not like you have to keep in a lane like a car. He was distracted or dozed off and missed a warning.


27 posted on 05/16/2015 4:22:05 PM PDT by Sacajaweau
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To: Duke C.
Let's say a thug tosses a bowling ball at Amtrak 188, presently moving at 70 MPH. That would be 15LBS times 88FPS which would equal 1,742,000 foot pounds of energy.

The ball's kinetic energy would be

0.5*15*(70*5280/3600)**2 = 79,053.3 foot-pounds

or about 0.0298 kilowatt-hours.

28 posted on 05/16/2015 4:22:15 PM PDT by cynwoody
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To: schurmann
Thanks for that.

We know from recent news that a train hitting an SUV can derail -- I was surprised to learn that. I have also arrived on a scene where a freight train passed through a semi trailer only minutes before - no derail; I suppose because it was a perfect broadside.

The smell of Kraft jelly and bar-b-cue sauce was heavy in the air, though -- that being the cargo in the trailer.

29 posted on 05/16/2015 4:24:13 PM PDT by 9thLife ("Life is a military endeavor..." -- Francis)
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To: MIchaelTArchangel

Thanks for your reply. The train was traveling at 70 MPH (88FPS) not the bowling ball. What would be the correct equation?


30 posted on 05/16/2015 4:25:19 PM PDT by Duke C.
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To: Duke C.

A car weighs a hell of a lot more than a bowling ball and would very rarely, if ever, derail a train. What derails trains is excessive speed in a turn for the bank angle, or problems with the rail. Loose rail, gap, foreign object attached to it, etc.


31 posted on 05/16/2015 4:25:48 PM PDT by Still Thinking (Freedom is NOT a loophole!)
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To: cripplecreek

whaaa?


32 posted on 05/16/2015 4:29:00 PM PDT by 9thLife ("Life is a military endeavor..." -- Francis)
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To: jacquej

The expert is bogus. There is no way a surprised jerk movement could instantly take a train from 50 to 100 mph that quickly. Or reduce speed from100 to 50 that quickly either.


33 posted on 05/16/2015 4:30:00 PM PDT by Secret Agent Man (Gone Galt; Not averse to Going Bronson.)
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To: Paladin2
A derailer attached to the track can do the job easily.

Shhh! I wasn't going to tell them about those!

34 posted on 05/16/2015 4:30:32 PM PDT by Still Thinking (Freedom is NOT a loophole!)
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To: 9thLife

My favorite is Train VS Tornado.

https://www.youtube.com/watch?t=11&v=EWH6QYClQvQ


35 posted on 05/16/2015 4:30:55 PM PDT by cripplecreek ("For by wise guidance you can wage your war")
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To: cripplecreek
Even at low speed, once a train starts crashing, it keeps crashing till its done.

Why do I get the feeling the occupation media believes this guy sat around all day with apples hitting him in the head and nothing else?



We are devolving as a species.
36 posted on 05/16/2015 4:32:24 PM PDT by PA Engineer (Liberate America from the Occupation Media.)
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To: Duke C.

F=MV\2 = republican’s fault


37 posted on 05/16/2015 4:32:41 PM PDT by Organic Panic
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To: Duke C.; All
Oh, well. Might as well get some rock on.

You're welcome!

38 posted on 05/16/2015 4:32:50 PM PDT by 9thLife ("Life is a military endeavor..." -- Francis)
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To: Still Thinking

Derailers look kinda heavy.


39 posted on 05/16/2015 4:34:02 PM PDT by Paladin2
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To: Talisker

Steal frames would seem to be a ‘hood thang.


40 posted on 05/16/2015 4:35:52 PM PDT by Paladin2
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