Recent content by walkinginwater

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    Undergrad Electric Stress between wires of a solenoid

    This Thread Has been Solved! Thanks for Meir Achuz Thanks very much, xez!
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    Graduate Have you ever heard Electric Field of one turn Solenoid?

    Have you ever heard "Electric Field of one turn Solenoid? hi, guys: Have you ever heard "Electric Field of one turn Solenoid"? Here is a example from MIT. Click on the weblink: http://web.mit.edu/6.013_book/www/book.html Click on the Chapter 10 in the left part of the screen...
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    Undergrad Electric Stress between wires of a solenoid

    hi, guys: I am reading some notes of Electromagnetism. It claims that for a helix solenoid with N turns of wire, the distance between the successive coil is \Delta a, the total vertical length of the solenoid is d. The artical claims that if we apply a voltage v to this solenoid...
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    Graduate How Can the Potential Due to an Infinitely Large Plate Be Justified?

    Ja, you got the point!
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    Graduate How Can the Potential Due to an Infinitely Large Plate Be Justified?

    hi, Pardesi: A point far from the point charge means that the electric potential caused by the point charge can be neglected; close to the plate means that its potential is near the potential of the plate. so it is also zero The key point is that the potential caused by the point...
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    Graduate Is Charge Conservation Violated in Spherical Volumes with Zero Current Density?

    This Thread Has been Solved! Thanks for Meir Achuz This Thread has been Solved! Thanks for the reply of Meir Achuz!
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    Graduate How Can the Potential Due to an Infinitely Large Plate Be Justified?

    Because of the symmetry, the field line above the plate will be upwards. Assume you move the electron along the field lines. The electron will always accelerated along the field lines, i.e., the potential will decrease. The key issue here is the word "infinitely", it means that you can move an...
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    Graduate Is Charge Conservation Violated in Spherical Volumes with Zero Current Density?

    Thanks for your answer! In fact, I continue to read the following sections from http://web.mit.edu/6.013_book/www/book.html" and I find in Section 7.8 and 7.9, there are more detailed explanation about this question. The conclusion is that: There are current density through the conduction...
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    Graduate How Can the Potential Due to an Infinitely Large Plate Be Justified?

    it is also zero!
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    Graduate Is Charge Conservation Violated in Spherical Volumes with Zero Current Density?

    hi, Meir Achuz: Thank you very much for your reply. But in fact I am confused over what you have said. In the website of MIT, it states that there is no current density in the material, i.e., there is no \vec J. But you said So it seems that your statement doesn't coincide with...
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    Graduate Is Charge Conservation Violated in Spherical Volumes with Zero Current Density?

    hi, guys: Charge conservation Violated? It seems to be: The charge density inside a spherical volume changes from \rho at t=0, after period of time \tau , the charge density decrease to 0. However, the author claimed that during the processing there is no current density in the material...
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    Undergrad Does a hydrogen baloon ascend faster than a helium baloon

    hi, Tony: Q_Goest is right. But the sentence, " It is a ratio of the mass given in the equation above, which is dependent on the balloon mass PLUS the mass of the gas." , has some problem. Because the ratio of the speed of the balloon is as the same as the "a", the acceleration upward. So...
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    Graduate Can anybody tell me what is Causal Solution

    Thanks Mentz114, I got the answer I want!
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    Graduate Can anybody tell me what is Causal Solution

    I am sorry English is not my native language, but is the "Causal" has such kind meaning? Can you tell me an online English dictionary to check that?
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    Graduate Hertzian dipole generating EM Waves.

    hi, polystethylene: Here is something you need: please read the weblink first; if you still have problem, please contact me! :smile:http://www.ece.rutgers.edu/~orfanidi/ewa/ch15.pdf"