How can I determine the strength of an electromagnet with an iron core?

[hover]

lately i have been really interested in electromagnets. i have been building small ones and i will eventually (at least i want to anyway) build a strong electromagnet (not some toy). from what i understand you can increase the strength of an electromagnet by adding more current, turning the wire more and adding a solenoid. for a start anyway i want to know the equations on how to determine the strength of an electromagnet with an iron core. the problem is for one of course, i don't know any equations on electromagnetic strength but two, i have a really hard time with all the different fraises used in the equations (ex. permeability). I just get totally confused. can someone please help CLEARLY explain the equation for the strength of an electromagnet? any help will be appreciated.
thx

 

[berkeman]

Welcome to FP, hover. Here's a good start from HowStuffWorks.com:

http://science.howstuffworks.com/electromagnet.htm

 

[hover]

Welcome to FP, hover. Here's a good start from HowStuffWorks.com:

http://science.howstuffworks.com/electromagnet.htm

good amount of info but I'm still missing the equation to calculate an electromagnet's strength

 

[berkeman]

good amount of info but I'm still missing the equation to calculate an electromagnet's strength

Hmmm. You're right, no equations. I'm being lazy today, so here's a better explanation from wikipedia with equations. Hope they help. Keep in mind that the force varies a lot with the separation of the electromagnet and the target metal piece.

http://en.wikipedia.org/wiki/Electromagnet

 

[hover]

Hmmm. You're right, no equations. I'm being lazy today, so here's a better explanation from wikipedia with equations. Hope they help. Keep in mind that the force varies a lot with the separation of the electromagnet and the target metal piece.

http://en.wikipedia.org/wiki/Electromagnet

i'm always lazy . thanks maybe i can finally figure how to calculate the strength

 

[Astronuc]

Hyperphysics is a good resource with equations as well as explanations.

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/solenoid.html

 

[waht]

you can increase the strength of the electromagnet by making it's length short but with lots and lots of turns. That would make a shape of a disk.

 

[hover]

Hyperphysics is a good resource with equations as well as explanations.

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/solenoid.html

i must be screwing up with the equation. somehow i get 3.17 tesla from a wire wrapped around a core 800 times with a core with 200 permeability and 1 amperes. it must be wrong. Can someone who knows what they're doing double check please?

thx

 

[Astronuc]

It would help if you write the formula/equation, and then show the values you are using.