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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?