Magnetic Attraction

Most recent answer: 10/22/2007

Q:
Can magnets attract/repel people? Thanks in advance! P.S.: I think it would be great if you put the date the question was asked and answered. THANKS AGAIN!
- Courthead
A:
Magnets don't attract or repel people very much. You can tell that easily. I have some very strong permannent magnets in my office, and I can't feel any force from them. On the other hand, I know that the force isn’t EXACTLY zero. People are made mostly of very weakly diamagnetic material, which means material that repels magnetic fields, regardless of which way the field points. On the other hand, we contain some paramagnetic molecules, which are attracted to magnetic fields, regardless of which way they point. Both effects are very weak, and they go in opposite directions. So the magnetic forces on people are very small.

I believe I’ve seen a picture of a very tiny frog levitating in a magnetic field, which would require that it be overall diamagnetic. For these purposes, people and frogs aren’t all that different, so I guess we are net diamagnetic too, but not enough to levitate, basically because we are too big.

Mike 4-11-02

(published on 10/22/2007)

Follow-Up #1: metals and magnetism

Q:
Is it possible for Magnets to repel/attract different metals other than gold, silver and aluminum? If so could you please name a couple that can, you don't have to I just want to know.
- Nobody (age 16)
Bozeman, Montana, United States of America
A:
Sure, every material is either repelled or attracted to magnetic fields. Except in the case of ferromagnetic materials (like iron) and superconducting materials (like very cold niobium), these effects are usually pretty weak.

For any particular element, you can check what type of effect there is on Wikipedia. For example, if you look up tinyou'll see that one crystal form is diamagnetic (repelled) and another is paramagnetic (attracted). The ones that show a strong attraction at room temperature will be called ferromagnetic.

Mike W.


(published on 02/12/2013)