There has been a great response to the basic question.
Rather than offer an answer, I would like to relate an incident which happened to me many decades ago.
I was, for a while, a Radio Officer (fancy name isn't it?) in the British Merchant Navy. Somebody on board had acquired some low power electrical device which needed a 110Vac supply, and they wanted to use it on board. The ship's supply was 220Vac. I calculated the value of a series resistor which could be used, and the power it would need to dissipate.
Our next port of call was a very small town, the name of which escapes me, on the southern bank of the St. Lawrence river. I went ashore to try to acquire the desired resistor. The first place I saw where I thought help might be available was a television repair shop.
Having not taken proper advantage of my long-suffering French teacher's efforts at school, I had some difficulty in conveying what I sought, and why, to the couple of technicians in the shop. I got there in the end.
It came as a great surprise that they had obviously forgotten, if they even knew in the first place, Ohm's Law, and struggled trying to verify the results of my (virtually mental) arithmetic to arrive at the numbers.
Why learn the basics? Hmmm .....