If shrunken down to micron size, a compass needle could wobble. (Courtesy: iStockphoto/tobias machhaus) A tiny magnetic needle just 10 μm long could be used to create a magnetic-field sensor that – if ...

In the days since GPS was invented, many of us have lost the skill of navigating by a good old compass and map. As a family ...

Safety note: the wire can get too hot to touch if you keep touching the terminals for too long. Can't see the video? Download an mp4 [21 MB] version of this video. Grab a compass, a coat hanger and a ...

A magnet (It can be a flat refrigerator magnet or a more powerful magnet, such as a rare earth magnet—the most common type is made of neodymium—which can be purchased at many hardware stores. A ...