very strong magnet ?

hi , and how can someone make a very powerful electric magnet , and also with small size ?

size matters when it comes to electro magnets buddy....the bigger, more power required, more powerful magnet

The relative strength of an electromagnet is measured by it's Ampere-Turns rating.

More turns and/or more current increase the strength.

You are limited on current by how much the wire is rated for (and heat build-up within the coil), turns are only limited by size.

The absolute strength also depends on the magnetic core and physical layout.

Depending what you mean by 'small', you probably cannot match the strength of a small neodymium permanent magnet.

Even for small industrial lifting on cranes, permanent magnets are used in preference to electromagnets.

MegaMan said:

hi , and how can someone make a very powerful electric magnet , and also with small size ?

Click to expand...

As I understand it, the amount of power in a magnet is only a small fraction of the power it took to manufacture the magnet in the first instance.

hgmjr

A very strong DC electromagnet can be made by machining a cup out of a steel billet, leaving a center pole that will accept a wire-wound bobbin.
You can experiment with various numbers of magnet-wire turns to get an idea of the strength factor, (amperes x turns).

Cheers, DPW [ Everything has limitations...and I hate limitations.]

MegaMan said:

hi , and how can someone make a very powerful electric magnet , and also with small size ?

Click to expand...

You can get rare earth magnets from Radio Shack or Edmund Scientific, and a lot of other science supply houses.

Also, you can disassemble an old hard drive and get some mighty powerful magnets.


Eric

Oops. Missed the Electro part.

Well the info is still good, anyway.


Eric

thanks people ^_^ ...

Ask Politely to any PC shop and get an Old, damaged Desktop HDD.

HDDs have one of the BEST EVER Rare earth magnets!
These are permanent magnets, not electros.

I ripped apart one and It was so hard even to get out!
Actually, i thought it was glued, but! Actually the magnet itself was so strongly attached to the casing.