Changing electric flux caused by a resistor

AI Thread Summary
Changing electric flux through an open surface generates a magnetic field, which is influenced by both capacitors and resistors. A resistor, like a light bulb, contributes to the magnetic field due to the current flowing through it and the time-varying electric field around it, effectively modeled as a capacitor in parallel. The resistance of most resistors increases with temperature, which can be explained by the increased atomic vibrations that reduce the average distance electrons travel before changing direction. This relationship highlights the interplay between temperature and resistance in electrical components. Understanding these concepts is essential for grasping the fundamentals of electromagnetism.
TheLil'Turkey
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I'm learning the basics about electromagnetism, including that a changing electric flux through an open surface causes a magnetic field. Obviously a capacitor causes this, but doesn't a resistor like a light bulb (whose resistance varies with temperature and therefore time) also cause this?
 
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Yes. Part of the magnetic field around the resistor comes from the current that flows through it. Another part comes from the time-changing electric field that spans it. You would model this as a capacitor in parallel with the resistor.
 
That makes sense. Thanks. I assume that the resistance of ALL resistors increases with increasing temperature. Is there a crude, classical physics model to understand why this is so?
 
I'm going to take a stab at answering my own question from post 3. I think that as the temperature goes up, the average distance an electron in a resistor travels before changing direction decreases because the atoms in the resistor are jiggling faster. Is that right?
 
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