Mathematicians do define their variable quite rigorously. Everything is so abstract, at some point you do just need to write down "this thing is a number". Problem with maths folks is rather that they get more creative with their other symbols. So, "this thing is a number" is actually written as "∃x, x ∈ ℝ".

But yeah, in the school/university physics I experienced, it was assumed that you knew that U is voltage, ρ (rho) is density, ω (omega) is angular velocity etc..
At one point, I had to memorize six pages of formulas and it felt like every letter (Latin, Greek, uppercase, lowercase, some Fraktur for good measure) was a shorthand for something.

[–] [email protected] 3 points 2 months ago (1 children)

I should specify when I say physical engineering I just mean chemical, mechanical, electrical, etc. (not software), rather than physics in theory/academia.

I guess engineers are applied physics (in a particular area each), and we need to distribute our deliverables to people who aren't necessarily experts in every discipline.

It just also makes sense to always define variables.

It's so funny because I've never seen voltage defined as U, and not V haha, proving how if you're going to have an equation, you'd better define everything, there's so many reused letters!

Thanks for sharing

[–] [email protected] 4 points 2 months ago (1 children)

U is definitely standard for a difference in electric potential in Europe. Thought to come from "Unterschied", difference. V refers to electric potential, which as wikipedia says so wisely, should not be confused with a difference in electric potential. Which North American notation does. At least it's not PEMDAS...

[–] [email protected] 4 points 2 months ago

There ya go (only used it up until highschool physics, in Australia, iirc), I definitely have no business reading anything regarding voltage then 😅

Thanks for sharing