Does a constant magnetic field cause a current?

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SUMMARY

A constant magnetic field does not induce an electric current; only a varying magnetic field can do so. The law of Biot-Savart states that the force on an electron is proportional to the charge and its velocity, meaning if the electron is stationary (v = 0), no force is exerted. To generate a current, one must either turn the magnetic field on and off, move the magnet, or move the conductor within the magnetic field, ensuring relative motion between the field and the conductor.

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  • Understanding of the law of Biot-Savart
  • Knowledge of electromagnetic induction principles
  • Familiarity with magnetic fields and their properties
  • Basic concepts of electric current and charge movement
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x86
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(1) I previously learned that a constant magnetic field causes a force on any electrons within its range. Clearly, this force would cause electrons to move. Isn't this creating a current?

(2) However, now apparently I am told that the only varying magnetic fields can create a current. I.e., turning a magnetic field on and off.

I am confused about this. Doesn't the first statement imply that a constant magnetic field can create a current?
 
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hi x86

The force on a charge (electron) from a magnetic field is proportional to q x v (law of Biot-Savart). If v = 0, ( ie. the magnetic field and the electron are stationary) there is no force.

(2) However, now apparently I am told that the only varying magnetic fields can create a current. I.e., turning a magnetic field on and off.
That's correct, so ...
1) turn magnetic field on and off
2) just moving the magnet ( field)
3) or by moving the conductor in a magnetic field.

There has to be relative motion between the field and the conductor

Dave
 
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