man, I was going to say exhaust, but that's not necessarily true. That one stumps me.

I don’t know anything about electrical physics. Never had to take a class on it.

Lol

The part of the wheel that is lower than the top surface of the rail

^

No, that's moving with the tracks

@GrumpyGabe gets a smartboi prize.

That’s more of a trick question. Lol

Not the flange that's lower than the surface of the rail @Jeremy-Retard

Think about it a minute

flange that's lower than the surface of the rail...

Train wheels have a part that runs on the inside of the track, lower than the surface, to keep it on the track.

that's still, angular wise, in step with the ground.

not moving backward w.r.t. the ground.

Nope.

explain

The axle is moving forward at the speed of the train, all points between the axle and point of contact with the rail are moving between train speed and zero.

Depends what you're measuring, but if you put a dot on the outermost point of the wheel, there will be a point in its rotation where that dot will be moving backward relative to the ground.

Points on the wheel with radius farther out than the point of rail contact move backwards with respect to the rail and the ground when they are underneath the rail surface.

That's impossible though, it's instantenous linear velocity might be faster than the forward motion of the train, but angularly it's not moving any faster than the contact point. That's more of a mathematical anomaly due to a higher radius.

Talking about the track-axis linear component of the motion.

I didn't say angular motion, I said "backwards with respect to the ground"

But it's not moving linearly.

A component of its motion is.

debatable, it's a circle.

And at its lowest point its entire motion vector points straight backward.

You wouldn't describe it's motion as linear

Ok, we can nitpick on that point but it's still kind of neat.

that's more of a riddle

If a pebble stuck on that part of the wheel came unstuck at that moment it would in fact fly backward.

Yes.

I said it was just for fun :-)

Yes, but that's a translation event, the motion it's experiencing translates.

translation isn't the right word.

It's just a neat kinematics riddle bud.

ya.

fine.

got me.

The kind of thing us lowly engineers love ;-)

I've turned myself into more of an electrical engineer than I started off as.

Oh yeah? What kind of physics do you do?