作者sleepinggod (别再幻想了)
看板Gov_owned
标题Re: [讨论] 电机乙第四题讨论
时间Wed Dec 31 22:53:15 2014
寄出释疑申请书後才找到这书 可惜好像不是正式的课本
有板友愿意把这本书写的写进释疑申请书吗?
electric flux 算出来的单位是 库伦
算式应该用 D ds 的积分
http://pokhara.academia.edu/AshokChhetry
http://ppt.cc/Wgv1
Faraday's experiments also showed, of course, that a larger positive charge
on the inner sphere induced a correspondingly larger negative charge
on the outer sphere, leading to a direct proportionality between the
electric flux and the charge on the inner sphere. The constant of
proportionality is dependent on the system of units involved, and we are
fortunate in our use of SI units, because the constant is unity. If electric
flux is denoted by Φ (psi) and the total charge on the inner sphere by Q,
then for Faraday's experiment
Φ = Q
and the electric flux Φ is measured in coulombs.
另一书本也是用这种的定义
《ELECTROMAGNETIC WAVES AND RADIATING SYSTEMS》Second Edition│Edward Conrad
Jordan, Keith George Balmain
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※ 编辑: sleepinggod (36.226.146.21), 12/31/2014 22:56:39
1F：→ ln123: 请把高斯大师的定理看仔细，不要拿其他文章申请疑义 12/31 23:01
在不同的单位系统 会有不同的写法
例如在 CGS Lorentz-Heaviside units. Electric flux = Q
Take a look at CGS Lorentz-Heaviside units. You will notice that the units
have been chosen such that the flux, calculated using the electric field, is
equal to the enclosed charge. There are some slightly different ways of
working with Maxwell's equations. Sometimes people like to formulate them so
that the inherent physics stands out without much distraction. Like the
Lorentz-Heaviside units, it is easier to work with flux equal to charge than
flux being equal to charge times some weird number. I prefer MKS myself
because then there is no conversion between SI units, which are usually used
for measurement, and the results of the equations.
https://www.physicsforums.com/threads/the-unit-of-flux-density.334061/
在相同的讨论串中也有人提到
着名的 CRC Handbook 也是用 D.ds的积分
In the CRC Handbook, they defined the electric flux to be the integral of the
electric flux density, not the electric field, and so that relationship would
still be correct.
我找不到Gauss 的原始论文, 搞不好他是用εE.ds 的面积分 = Q,
在均匀介质中可以把 ε搬出积分然後移到等号右边,
才会变成 E.ds的面积分 = Q/ε 这只是特例(在均匀介质中)
※ 编辑: sleepinggod (36.226.146.21), 12/31/2014 23:27:04
※ 编辑: sleepinggod (36.226.146.21), 01/01/2015 00:47:32
※ 编辑: sleepinggod (36.226.146.21), 01/01/2015 00:54:33
※ 编辑: sleepinggod (36.226.146.21), 01/01/2015 00:55:14
※ 编辑: sleepinggod (36.226.146.21), 01/01/2015 01:00:54
2F：→ ln123: 你可以把当年高斯提出电通量一辞的论文找出来？看他当年是 01/01 01:02
3F：→ ln123: 定义EA还是DA？ 01/01 01:02
※ 编辑: sleepinggod (36.226.146.21), 01/01/2015 01:33:32
4F：→ sleepinggod: l大 如果你有高斯的论文 可以分享吗? 01/01 01:34