Electricity and magnetism (magnitude of magnetic field)

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A 1000-turn toroidal solenoid with a central radius of 4.2 cm and a current of 1.7 A generates a magnetic field calculated using the formula B=(μ0)(I)/(2∏)(r), resulting in a value of approximately 1.43x10^-8 T. The discussion emphasizes that each loop of wire contributes to the total magnetic field, following the superposition principle, meaning the fields from multiple loops add together. There is some confusion regarding the magnetic field at the center, with claims that there is no current there, but it is clarified that the total field is a result of all loops contributing. Participants recommend using resources like HyperPhysics to better understand these concepts. Understanding how magnetic fields work is crucial for solving related problems effectively.
swankymotor16
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A 1000-turn toroidal solenoid has a central radius of 4.2 cm and is carrying a current of 1.7 A. What is the magnitude of the magnetic field inside the solenoid at the central radius? (μ0=4∏×10^-7 T ∙ m/A) r= 4.2cm= 0.042m

B=(μ0)(I)/(2∏)(r) ⇔ (4∏×10^-7)(1.7)/(2∏)(0.042) ⇔ 1.43x10^-8 T? Or does the 1000-turn toroidal affects in the magnetic field in some sort of a way?
 
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Would you expect a long coil of wire to have a different field to a single loop?
What would you expect for the field due to two loops of current?
 
yes. But, how different will be? Is there a formula for it?
 
Don't go by formulas, use your understanding of how magnetic fields work - if one loop had a field of B, and you added another one the same, what do you think would happen to the field?
 
that's the problem! I don't know how magnetic fields work! I have a bad teacher, and I'm running out of time! Another source told me that there's no current in the center, and by Ampere's Law the current in the center is zero. is this true?
 
that's great! I was missing the N, the 1000 turns. thank you!
 
That's cool ... the lesson here is that electric and magnetic fields add together. This is called "the superposition principle". Make sure you work through the hyperphysics pages to bring you up to speed.
 
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