When are Maxwell Equations Generally Used?

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
4 replies · 3K views
solarblast
Messages
146
Reaction score
2
See Subject. What engineering tasks do they regularly get used? Building high-frequency components, antennas?
 
Physics news on Phys.org
I imagine Transformers, coils in a car , solenoids, sub stations. Electric motors. alternators, And there are lots more. Microphones, speakers any circuit or things that have to do with current or charge.
 
I would think for many purposes that common electrical laws would do just fine, Ohm's Law, Thevenin's and Norton's Laws. This is another way, perhaps, of recognizing the boundary between conventional laws and Maxwell's equations. I think his equations embody simpler notions, but using them there would be a waste. I'm thinking of something analogous to general relativity and Newton's laws.
 
solarblast said:
I would think for many purposes that common electrical laws would do just fine, Ohm's Law, Thevenin's and Norton's Laws. This is another way, perhaps, of recognizing the boundary between conventional laws and Maxwell's equations. I think his equations embody simpler notions, but using them there would be a waste. I'm thinking of something analogous to general relativity and Newton's laws.

You're right. Even in antenna design you more often use the free-space Green's function for radiation than Maxwell's equations directly. But you do use them directly especially when working in any material media.

In transformer design you have equations in the can that are based on or derived from Maxwell's equations but are easier to use.

The modern 3D software that analyzes any of these things numerically always solves Maxwell's equations but of course it's all under the hood.