Solenoid with a magnetic core problem

[physstudent1]

Homework Statement

A long solenoid with 70.0 turns of wire per centimeter carries a current of 0.100 A. The wire that makes up the solenoid is wrapped around a solid core of silicon steel (Km=5200). (The wire of the solenoid is jacketed with an insulator so that none of the current flows into the core.)

For a point inside the core, find the magnitude of the magnetic field B due to the solenoid current.

Homework Equations

The Attempt at a Solution

I used the regular solenoid equation B = munaught(n)I but i replaced munaught with munaught*5200 this gave me 4.55 but that isn't the right answer?

 

[marcusl]

I get the same answer.

BTW, no need to double post. This is the correct forum for this question.

 

[chenlwbdh]

Hi:

How can I generate max magnetic field from 2" x 4" core surface?

Any material can isolate magnetic field?

Regards,
Eugene