Does a conductor create magnetic field when moving?

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Discussion Overview

The discussion centers on whether a conductor generates a magnetic field when it is moved, particularly in relation to the movement of electrons within the conductor and the implications of their speed. Participants explore the differences between electron movement in a closed circuit versus when the wire itself is in motion.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that a magnetic field is created when electrons move in a conductor, noting that in a closed circuit, electrons move at a speed of a few mm/s.
  • There is a question about whether moving a piece of wire would generate a magnetic field, with some expressing skepticism about this possibility.
  • One participant suggests that when the wire is moved, both electrons and protons are displaced, but the effects may cancel due to their opposite charges, leading to a focus on the movement of free electrons.
  • Another participant emphasizes that the number of electrons moving through the conductor in a given time is what matters, rather than their speed.
  • Questions arise regarding the definition of "slow" in the context of electron movement, prompting a request for clarification on the drift velocity of electrons.
  • A participant provides a reference to a Wikipedia article on drift velocity, which includes numerical examples illustrating the speed of electrons in a wire with a specific current.
  • Several participants express interest in the concept of drift velocity and share their experiences of discovering related information.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether moving a conductor generates a magnetic field, and there are competing views regarding the relevance of electron speed versus the number of electrons moving.

Contextual Notes

Discussions include references to drift velocity and its implications, but there are unresolved questions about the relationship between electron movement and magnetic field generation.

GhostLoveScore
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Magnetic field is created when electrons move in the conductor, as far as I know. In the electric circuit electrons move with a speed of few mm/s when the circuit is closed.

So, if I took a piece of wire and moved it, would it generate magnetic field? I suspect not, but I am wondering what is the difference when electrons are moving in the electric field inside the wire, or when they are moving when we move the wire.
 
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GhostLoveScore said:
Magnetic field is created when electrons move in the conductor, as far as I know. In the electric circuit electrons move with a speed of few mm/s when the circuit is closed.

So, if I took a piece of wire and moved it, would it generate magnetic field? I suspect not, but I am wondering what is the difference when electrons are moving in the electric field inside the wire, or when they are moving when we move the wire.
When you move the wire, you are moving electrons and also the protons in the nucleus. As these charges are opposite polarity, the effects cancel out. When a current flows in a wire, the free electrons do the moving, whilst the remainder of the atoms, which are positive, are heavy and do not move much. So we see a movement of negative charge in this case.
It is worth mentioning that when the electrons move, it is slow, but the charge involved is very great.
 
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GhostLoveScore said:
Magnetic field is created when electrons move in the conductor. In the electric circuit electrons move with a speed of few mm/s when the circuit is closed.

All that matters is how many electrons move through the conductor in a given time.
The speed of the electrons (how far in a given time) is irrelevant.
 
When you say the movement of electrons "is slow", how slow is that?
 
Beanyboy said:
When you say the movement of electrons "is slow", how slow is that?
See https://en.wikipedia.org/wiki/Drift_velocity, under Numerical example.

In their calculation, the electrons in a 2mm diameter wire with a 1 A. current are moving at about .02 mm/sec.
 
Wow! Fascinating article. Just read over the gist of it and even with my rudimentary math skills, the numbers are fascinating. Thanks for sharing. I'd never have thought to look up "drift velocity".
 
Beanyboy said:
I'd never have thought to look up "drift velocity".
I wouldn't have, either. I looked up "electron speed in a wire" and followed a link on the wikipedia page to their page on "drift velocity."
 

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