Can you solve the MAGNET RIDDLE? ft YouTube CEO Susan Wojcicki

Use he string and hang it. Earths magnetic field with help determine. 

If it’s a strong enough magnet move it very fast around any metallic surface. You should feel eddy current effects. 

Move it around the dry wall you can feel the nail behind the walls. 

If you have something burner then heat one up for like 15 minutes and the magnet would loose some of its magnetism. 

If there are copper wires and battery power source handy then using the copper wire make an electro magnet. It’s easy then to identify the magnet.