What happens when a magnet gets close to an object that may have a weak magnetic field?
Hopefully any senior who has gone through E&M should be able to answer that the weaker magnet can be affected and changed by a stronger magnet.
A common way of searching for meteorites is to use magnets, since rocks from space are likely to have some iron in them. But this also means that using a magnet can change any magnetic field the meteorite may have, thus erasing valuable scientific information about the magnetism in our solar system that that rock had carried for perhaps billions of years before finally crashing into the earth. This is a problem for scientists who need meteorites to study and collect information about the ancient solar system! And this is a problem since so many meteorites are found by amateur 'hunters'.
So basic physics we learn in high school make a difference in real life research efforts!
