What happen to a metal bar near a Van de Graaff?

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    Metal Van de graaff
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Discussion Overview

The discussion revolves around the effects of placing a metal bar near a Van de Graaff generator, specifically regarding the potential for magnetization and changes to the internal molecular structure of the metal due to the electrostatic field generated by the device. Participants explore concepts related to electric polarization, magnetization, and the interaction of electric fields with materials.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires whether a metal bar can be magnetized when placed near a Van de Graaff generator and questions the effects on its molecular structure.
  • Another participant explains that the metal bar has a finite capacitance and that its potential will match that of the Van de Graaff, suggesting that the charge density can be calculated based on this capacitance.
  • Some participants clarify that the Van de Graaff generator produces electrostatic fields, which can lead to electric polarization of the metal bar but not magnetization, as magnetization requires a magnetic field.
  • There is a question about whether placing the Van de Graaff near the ground for an extended period could result in the ground being magnetized by the positive charges from the generator.
  • One participant raises the idea that if the electric field from the Van de Graaff is strong enough to produce a spark to the ground, it might generate a magnetic field capable of polarizing a small area on the ground's surface.
  • A later reply critiques the understanding of the original poster, suggesting that their inquiries reflect a misunderstanding of basic physics principles and labeling the ideas as pseudoscience.

Areas of Agreement / Disagreement

Participants express differing views on the possibility of magnetizing the metal bar and the nature of the interactions involved. There is no consensus on the implications of the electric field generated by the Van de Graaff generator, and some participants challenge the foundational understanding of the concepts discussed.

Contextual Notes

Some participants appear to conflate electric polarization with magnetization, leading to confusion about the effects of the Van de Graaff generator on the metal bar. There are unresolved questions regarding the conditions under which electric and magnetic fields interact.

oem7110
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When I place a metal bar near a Van de Graaff, which generate hugh amount of positive charges on its surface, if I hold it for a period of time, will it be possible to magnetize this metal bar? what happen to its internal molecula structure?
Does anyone have any suggestions?
Thanks in advance for any suggestions
 
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The metal bar has a finite (and VERY small) capacitance. The potential of the bar will match that of the Van de Graaff, and the charge density on the surface could be calculated based on the capacitance.

The Van de Graaff can generate fairly high voltages, but not infinitely high - not high enough to cause a breakdown at a molecular level of a metal.
 
uby said:
The metal bar has a finite (and VERY small) capacitance. The potential of the bar will match that of the Van de Graaff, and the charge density on the surface could be calculated based on the capacitance.

The Van de Graaff can generate fairly high voltages, but not infinitely high - not high enough to cause a breakdown at a molecular level of a metal.

What if I place Van de Graaff near the ground for a long period, will the ground have higher capacitance to be magnetized with this positive charges from the Van de Graaff?
Do you have any suggestions?
Thanks you very much for any suggestions
 
oem7110 said:
When I place a metal bar near a Van de Graaff, which generate hugh amount of positive charges on its surface, if I hold it for a period of time, will it be possible to magnetize this metal bar? what happen to its internal molecula structure?
Does anyone have any suggestions?
Thanks in advance for any suggestions

I sounds like you are mixing up electric polarization with magnetization.

What would happen is that when the bar is near the surface of the Van de Graaff generator, the positive charge of the generator would create an electrostatic field which would attract the electrons in the metal causing the side closest to it to become negatively charged compared to the other side (electric polarization). Magnetization happens when a magnetic field aligns the tiny magnetic dipoles of a material (magnetic polarization) and some of the dipoles stay aligned after the field is removed.

Since Van de Graaff generators only generate electrostatic fields, they cannot magnetize an object, no matter how long it's held near it.
 
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Jasso said:
Since Van de Graaff generators only generate electrostatic fields, they cannot magnetize an object, no matter how long it's held near it.

The electrostatic force experienced by positive charges from Van de Graaff generators is the interaction between negative charges from the ground's surface. The electric field is the force per charge at a given location and is perpendicular to Van de Graaff generators' surface. Whenever there is an electric field, would it be true that there is also a magnetic field existed?

If the magnitude of an electric field from Van de Graaff generators is strong enough to produce a spark to the ground, will it generate enough magnetic field to polarize a small local area on the ground's surface?
 
Last edited:
Any suggestions?
 
oem7110, I do have a suggestion: study and learn basic physics. You demonstrate a lack of understanding of the fundamentals.
Above, you wanted to magnetize concrete using voltage. Then you wanted to magnetize water using voltage. Now, you want to magnetize a metal bar using voltage.

In all three tries here in this forum you have been told by experienced scientists and engineers that you are talking "pseudoscience". That means, in case you can't handle words with more than ten letters, science fiction, or, pure bs.

This is an opportunity for you to learn from this where your understanding is faulty.
 

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