Physics Help Forum some formulas

 Electricity and Magnetism Electricity and Magnetism Physics Help Forum

 Jul 9th 2017, 10:39 PM #1 Junior Member   Join Date: Jul 2017 Posts: 27 some formulas dH=dl/dt dB=dl/dx dE/dB=-dx/dt dD=dl/dx dH/dD=-dx/dt H - magnetic field strength; B - magnetic flux density; E - irradiance; D - electric displacement field. Please, have a look at these equations. Are they correct? I can't grasp the idea. Any explanations? I need some intuitive understanding of this formulas (if they are correct) and some knowledge about how they are derived... I will be grateful for every comment... Wish you everybody a nice day!!
 Jul 10th 2017, 12:15 AM #2 Senior Member   Join Date: Nov 2013 Location: New Zealand Posts: 534 Not sure but they remind me of Maxwell's equations: https://simple.wikipedia.org/wiki/Maxwell%27s_equations topsquark likes this.
Jul 22nd 2017, 06:20 PM   #3
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 Originally Posted by DesertFox dH=dl/dt dB=dl/dx dE/dB=-dx/dt dD=dl/dx dH/dD=-dx/dt H - magnetic field strength; B - magnetic flux density; E - irradiance; D - electric displacement field. Please, have a look at these equations. Are they correct? I can't grasp the idea. Any explanations? I need some intuitive understanding of this formulas (if they are correct) and some knowledge about how they are derived... I will be grateful for every comment... Wish you everybody a nice day!!
No. They are not correct.

kiwiheretic - I saw where he got the. The author is an idiot. His derivation was sinners in hell. That'll teach them. Lol The author uses d for he partial derivatives. Unfortunately our new friend DesertFox uses bold for things other than vectors.

Jul 22nd 2017, 10:40 PM   #4
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 Originally Posted by Pmb No. They are not correct. kiwiheretic - I saw where he got the. The author is an idiot. His derivation was sinners in hell. That'll teach them. Lol The author uses d for he partial derivatives. Unfortunately our new friend DesertFox uses bold for things other than vectors.
The use of bold was my idea. I decided to mark the equations, because they were the things which I wanted to check whether they are correct or not. Now I know this was a bad idea and very confusing.
They are not written in bold in the original text. I just wanted to know, for example, whether dH=dl/dt is correct and if NOT- for what reason....

Jul 22nd 2017, 10:44 PM   #5
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 Originally Posted by DesertFox The use of bold was my idea. I decided to mark the equations, because they were the things which I wanted to check whether they are correct or not. Now I know this was a bad idea and very confusing. They are not written in bold in the original text. I just wanted to know, for example, whether dH=dl/dt is correct and if NOT- for what reason....
Ah ha! I finally understand. In forums we have no need to make such a distinction because all equations are of importance to us. In fact we focus on them.

By the way, when I was talking about the idiot author I was talking about the author of the text you got those from. I'd never address a member of a forum like that. Okay?

Jul 22nd 2017, 10:53 PM   #6
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 Originally Posted by Pmb Ah ha! I finally understand. In forums we have no need to make such a distinction because all equations are of importance to us. In fact we focus on them. By the way, when I was talking about the idiot author I was talking about the author of the text you got those from. I'd never address a member of a forum like that. Okay?
Sure, I understood

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