Obviously there needs to be a transition, but at some point you go from physics to engineering. I suppose it depends what specialty in physics you go into. Nobody can specialise in everything.
(I didn't introduce it - it was already being used).
Engineering: practical implementation
That’s how it goes in my brain. It’s physics until we can build it reliably, then it’s engineering.
The benefit of taking such a class or reading such a textbook is that these things have been studied extensively, we have good models for them, and it is useful to know because people are still doing fundamental research on it to this day or working on phenomena that are closely related.
1. The boundaries between disciplines are where they are in part by historical accident, and in part because that's what the people working in them find useful - there is no actual fact of the matter.
2. We don't actually know the underlying microprocesses of anything. Effective theories are all we have, and there's no fundamental difference between an effective theory for the vacuum (if it is a vacuum) and one for, say, the bulk of a semiconductor.
This is true of all categories, so not a helpful comment. I suspect someone has a good enough definition.
I think the more relevant aspect is that to reach the frontier in a wide array of fields you a solid grounding quantum physics (and several other "new" -- i.e. within the last century or so -- topics) that have displaced more "old-fashioned" topics like continuum mechanics.
if you can understand the PDEs of GR and QFT, you can apply it to this too
But I probably like abstractions like this more than most people.
Oddly, undergraduate physics also seems to be missing another, arguably even more fundamental, tensor: the moment of inertia. You can get quite far (in three dimensions, and only in three dimensions) by thinking of rotation as a vector. (Or a quaternion if that floats your boat.) But you can’t get very far by pretending that the moment of inertia is a scalar, and you get very confused very quickly if you treat it as three scalars in the magical coordinate system in which you can write it like that.
Classical ( non relativistic ) field theories by now are undergrad engineering topics, but there are only a few quantum engineers.
Most of the non quantum topics in modern undergrad physics curricula, is needed to make sense of quantum[ thermodynamics, filed theory, optics, something ]
Hydraulics are everywhere. Ever used a sink? Flushed a toilet? Contemplated an air filter? Felt both sides of a small fan? Wondered how, exactly, a utility pump causes water to go in the inlet and out the outlet, and tried to read the manufacturer’s spec? Contemplated that the ripples when you throw a rock in an actual pond really don’t resemble the average “look I made water in WebGL” animation very much?
And more fancily, and very much in “Physics”, cosmological models usually model the universe as being full of a spatially varying continuous fluid. Stars are plasma or weirder things, and those are fancy fluids.
Yet, for some reason, the basics are missing from “Physics”. You can sometimes find them in mechanical engineering departments, and Feynman covers it a bit in his lectures.