Do magnets lose their properties ? When?
Magnets lose their properties if they are heated or dropped from a height or hit with a hammer.
Magnets lose their properties when they are placed near Cellphone, Computer, DVDs. These objects will also get affected by magnetic field.
Activity 3: Make your own magnetic compass
Insert the magnetized needle, that you made in the activity 2, in to two styrofoam balls (Thermocol balls) and place the needle in bowl of water. Test whether the floating needle is always turned in rest on north - south direction.
Note: If you don't have styrofoam balls you can use dry leaf or a cork piece.