Name: Dianne L.
At the library at which I work, the end of the Summer
Reading program is upon us. Two of the prizes that children can
receive are magnets and small, inexpensive, belt-clip compasses. Guess what
got stored together in the same box? Now the compasses point every which
way. Is there any way to correctly repolarize a compass, or are they
destined for the trash bin?
As I assume that these are pretty cheap compasses, the pointer is fully
enclosed and inaccessible. I would place them in the trash.
A neat experiment to make a compass is to stroke a needle with a magnet
and push it through a cork. Place the cork in water and the needle will
align with the earth's magnetic field. With your compasses, you would
need to use a magnet to realign each compass pointer's magnetic field in
a similar fashion. I am not sure it is worth it.
They may not have been harmed at all. Why not store them in a box with a
much more powerful magnet inside. The little fellows will automatically
align themselves with big brother's field and all will live happily
together. In doing so, you will be overpowering the earth's magnetic field
and forcing the little fellows to follow the field directions of the big
guy rather than trying to follow the chaotic lead of each other.
Click here to return to the Physics Archives
Update: June 2012