I don't understand the concept of divergence. Can anyone explain this concept in a vivid way and its relationship with inflow and outflow?

一沙一世

I don't understand the concept of divergence. Can anyone explain this concept in a vivid way and its relationship with inflow and outflow? [Copy link]

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I don't understand the concept of divergence. Can anyone explain this concept in a vivid way and its relationship with inflow and outflow?

maychang

Divergence cannot be explained in a few posts, even with a "visual explanation". This is because it involves several more basic concepts, such as vectors, vector fields, flux, Gaussian surfaces, etc. In particular, general physics in engineering usually only talks about electrostatic fields and static magnetic fields, but not about field gradients, curl, divergence, etc.

maychang

If you want to "explain this concept in a vivid way and its relationship with inflow and outflow", it is recommended to review the electromagnetic part of general physics first, such as the second volume of General Physics by Cheng Shouzhu and Jiang Zhiyong (you can skip the part about electric current, including Kirchhoff's laws, etc. and induced electric field). After reading this part carefully and understanding the flux of the vector field, I can tell you about divergence and even the physical images of gradient and curl.

maychang

The second volume of General Physics by Cheng Shouzhu and Jiang Zhiyong talks about electrostatic fields and magnetic fields, as well as electromagnetic induction, but does not talk about gradient divergence and curl, and directly talks about Maxwell's equations. Therefore, Maxwell's equations are not required for students to fully understand in this book, just knowing them is enough.

maychang

There was a post on an electronics website that said curl is a "winding" field. A Mr. HWM immediately gave a field of all straight lines, but did not explain it. I explained this field of all straight lines from a physical sense, showing that a field of all straight lines can also have non-zero curl, and also showing that curl is a vector field. However, I don't know if the original poster understood it.

一沙一世

maychang posted on 2022-7-24 11:39 There was a post on an electronics website saying that curl is a "winding" field. A Mr. HWM immediately gave a straight...

Thank you very much. I am holding a copy of

read through.