Electrons cannot sense electrostatic force?

In summary, the conversation discusses the lack of voltage or current when connecting a multimeter ground to the negative terminal of a DC power supply or charged capacitor for only 1ms. It is explained that this is due to the open circuit causing zero current flow, which is different from the current flow in an antenna. The conversation also touches on the complexity of dealing with electromagnetic forces and the limitations of digital multimeters in detecting small average currents. It is suggested that using a digital storage oscilloscope with a high sample rate may provide better results. The impact of capacitance and resistance on the visibility of pulses is also mentioned. The conversation concludes with the acknowledgement that without a circuit diagram, it is difficult to discuss the specific situation in detail.
  • #1
thomasj
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Why there is not voltage or current just for 1ms if I connect a multimeter ground to the negative terminal of a DC power supply or charged capacitor? Why electrons in measure lead and DMM device cannot sense a bulk of electrons (or lack of it)? I tried with an 5kV DC power supply too. In an antenna they sense this force and move from or to the source.
 
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  • #2
thomasj said:
Why there is not voltage or current just for 1ms if I connect a multimeter ground to the negative terminal of a DC power supply or charged capacitor?
Because multimeters work on current flow and you are talking about an open circuit with zero current flow.
 
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  • #3
phinds said:
Because multimeters work on current flow and you are talking about an open circuit with zero current flow.
But an antenna also an open circuit and there is current in it.
 
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  • #4
thomasj said:
But an antenna also an open circuit and there is current in it.
This is a good observation and shows the danger of confusing steady state conditions (DC) with changing ones (AC /Step Functions / Pulses). EM can't be dealt with with simple, one-line statements. Even JC Maxwell needed Three Equations!
 
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  • #5
sophiecentaur said:
This is a good observation and shows the danger of confusing steady state conditions (DC) with changing ones (AC /Step Functions / Pulses).
Interesting but can you explain, please? I tried to use pulse DC with a push button but no effect.
 
  • #6
thomasj said:
Interesting but can you explain, please? I tried to use pulse DC with a push button but no effect.
The title of your thread refers to Electrostatic Forces. When the forces are not Static, things are different. The reason that your DMM recorded nothing will be a combination of factors. Firstly, a Digital Analogue Converter (the heart of a DMM) takes samples and gets an average over its sample interval. The total charge that passes with an experiment like yours will depend on the Capacitance of the apparatus. The peak current could be fairly high (easily detectable by your DMM) but the average may be very small. It's the sort of thing that a 'clunky' analogue meter might show you by a tiny twitch of a needle. (Newer doesn't always mean better. :wink:)
 
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  • #7
sophiecentaur said:
... but the average may be very small. It's the sort of thing that a 'clunky' analogue meter might show you by a tiny twitch of a needle. (Newer doesn't always mean better. :wink:)
Thanks, I suspect this. And if I would use a DSO instead? Sample rate of that device is high enough I guess. Shorter time period's average could be better here.
 
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  • #8
thomasj said:
nd if I would use a DSO instead? Sample rate of that device is high enough I guess.
Depending on the capacitance of that wire, picoseconds or nanoseconds might be needed to see the spike.
 
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  • #9
anorlunda said:
Depending on the capacitance of that wire, picoseconds or nanoseconds might be needed to see the spike.
The series R would be relevant, wouldn't it? RC time constant would be longer
 
  • #10
sophiecentaur said:
The series R would be relevant, wouldn't it? RC time constant would be longer
The way the OP stated it, is is the R of a short piece of wire.

But time constant alone does not make it visible. It is area under the curve, i.e. energy, that makes the difference between visually visible or invisible pulses.
 
  • #11
anorlunda said:
The way the OP stated it, is is the R of a short piece of wire.

Again, there is no circuit diagram to enable us all to be discussing the same situation. I assumed that a meter was in series.
 

1. What is electrostatic force?

Electrostatic force is a fundamental force of nature that describes the attraction or repulsion between electrically charged particles, such as electrons and protons.

2. Why can't electrons sense electrostatic force?

Electrons are negatively charged particles that are constantly in motion, making them unable to sense the electrostatic force exerted by other charged particles. This is because they are already experiencing the force of their own movement and are not affected by the force of other particles.

3. How do electrons interact with other charged particles if they cannot sense electrostatic force?

Electrons interact with other charged particles through the exchange of virtual photons, which act as carriers of the electrostatic force. This is known as the electromagnetic force, which is responsible for all electric and magnetic interactions.

4. Can electrons ever experience electrostatic force?

Yes, under certain conditions, electrons can experience electrostatic force. For example, when an external electric field is applied, the electrons will be affected by the force and will move in a specific direction.

5. Why is it important to understand that electrons cannot sense electrostatic force?

Understanding that electrons cannot sense electrostatic force is crucial in the study of electricity and magnetism. It helps us to understand the behavior of charged particles and the interactions between them, which is essential in fields such as electronics, materials science, and particle physics.

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