- #1

EmeraldPlatypus

- 1

- 0

F=((NI)^2 A mu0)/2X^2.

N is turn number, I is current, Mu0 is permeability of free space, A is the area of the core and X is the distance from the electromagnet.

I take issue with for a number of reasons. Firstly, surely it depends on the material I am trying to attract. I know from experience that a magnet that can lift a few hundred gram of iron can barely lift a gram of ferrofluid, and the equation just gives a flat force.

It also doesn't account for any core material. As far back as GCSE I have been told that "an iron core makes the electromagnet stronger" Well how much stronger? And to what property of the material does this strength increase correlate??

Can anyone give me an equation that shows some dependence on core material and the material that will be attracted to the electromagnet, as well as all the stuff listed in the (as I see it) in complete EM force equation