Quick question about the flux density through a solenoid.

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SUMMARY

The flux density through a solenoid is defined by the equation B = μ₀ n I, where n represents the number of turns per unit length and I is the current. This formula indicates that the magnetic field strength B is uniform within the solenoid, similar to the uniform electric field in a parallel-plate capacitor. However, measurements taken with a Hall probe reveal that the magnetic flux density B decreases as one moves from the center of the solenoid towards its ends, indicating that the formula applies primarily within the central region of the solenoid where the field is uniform.

PREREQUISITES
  • Understanding of electromagnetic theory, specifically solenoids
  • Familiarity with the concepts of magnetic flux density and magnetic field strength
  • Knowledge of Hall probe operation and measurement techniques
  • Basic grasp of the relationship between current, turns per unit length, and magnetic fields
NEXT STEPS
  • Study the derivation and applications of the formula B = μ₀ n I in various solenoid configurations
  • Research the behavior of magnetic fields in different geometries, such as toroids and coils
  • Explore the principles behind Hall effect sensors and their use in measuring magnetic fields
  • Investigate the impact of solenoid length and current variations on magnetic field uniformity
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Students in physics, electrical engineers, and anyone involved in experimental physics or electromagnetic applications will benefit from this discussion.

rock.freak667
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Homework Statement



the flux density through a solenoid is given by

[tex]B=\mu_o n I[/tex]

Where n is the number of turns per unit length.

The number of field lines per unit area is proportional to B.

I am assuming that at or near the centre of the solenoid the number of field lines per unit area decreases so B decreases.
If that is true, then how come the formula stated above doesn't account for distance from the centre of the solenoid?
 
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That's not the flux through a solenoid, that's the magnetic field strength. The magnetic field is uniform inside the solenoid (like how a parallel-plate capacitor has a uniform electric field between the two plates).
 
Magnet flux density is the same as field strength?

The reason I ask is that there is a question in which a Hall probe measures tehe magnetic flux density in a solenoid. They take measurements fromt the centre of the solenoid(x=0cm) until the end of the solenoid(x=16cm).
The results showed that as the x increases, B decreased.
Then the question asked "What conclusions can be made about the (i) the region where the formula ([itex]B=\mu_0 n I[/itex] applies"
 

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