I know how big a moose is. I've been uncomfortably close to them more than once.
But I also know how big a train is, and I still don't see it. I know that in terms of mass, a train is to a car as a car is to an empty beer can. A car can derail a train, but won't very often. A moose might weigh as much as a small car, but has less stiff metal in the frame. It still might derail a train... but not very often.
Bear and moose have plenty of fat et al. The derailment isn't a simple metal-on-metal action, it's a metal-on-moose-on-metal interaction. The moose is skin-protein-fat-bone-fat-protein-skin. Do the math.
I'm not sure what math you think I'm supposed to do, but I know that a railroad wheel has ten tons of weight on a strip a couple of inches wide. If a moose is thin enough to not get knocked aside by the snowplow[1], it's probably thin enough to get cut through by the wheel.
Still waiting for some evidence for the claim that "moose are responsible for quite a few train derailments".
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[1] Yes, I know that not all railroad engines have them. Most that don't have a flat plate that still gets down pretty close to the track.
But I also know how big a train is, and I still don't see it. I know that in terms of mass, a train is to a car as a car is to an empty beer can. A car can derail a train, but won't very often. A moose might weigh as much as a small car, but has less stiff metal in the frame. It still might derail a train... but not very often.