Magnetism. Magnetizing. Can Big Honking Things Be Magnetized ?

Question

When goofing around with a magnet, one will find that some small stuff (with some Fe in it) will become magnetized (to whatever degree).

What would be required to magnetize something of pretty substantial size - like a fire hydrant or a manhole cover or the side of a car ?

All kinds of stuff could be magnetized - just for laughs - if it's practical to do so. (I don't need admonitions about the potential damage/problems that magnets can cause).

And would it stay magnetized ?

Answer 1

go to a junk yard and view the operasting of an electromagnetic scrap-crawler-crane at work and see the action created and used-i tried to buy a baby bantem from the local yard just for unloading junk i was purchasing to resell as my warehouse had a rail line in the backyard and the junk yard refused to sell to compitition, but there fun to watch the mag hit the button and the object jump at it-

Answer 2

Whole parts of the Earth are magnetized, that is how they can determine things like continental drift or the movement of rock strata.

The Earths magnetic field is pretty steady, so if huge amounts of molten magnetic rock solidify when exposed to that magnetic field they will be magnetized to coincide with the Earths magnetic field.

That is how they can make really huge permanent magnets ... you heat it up under the influence of a stong magnetic field and let it solidify.

Answer 3

The earth is, so I suppose with a little thought you could get a hydrant magnetized.

Answer 4

Magnets are cool, but they lose their magnetism over time. Electromagnets are WAY cooler because they keep their magnetism for as long as the current (DC only, please) is on. Try "Electromagnets " on Google, or follow this link. Fun Stuff!!!
http://www.howstuffworks.com/electromagnet.htm