Build a working speaker from a paper cup, magnet, and wire
Plug it into your phone, music plays from a cup. They built audio.
How to do it
Wrap enameled copper wire into a flat coil about 1 inch in diameter, 50 turns. Sand both lead ends to remove enamel. Glue the coil to the bottom of a paper cup. Glue a neodymium disc magnet to a flat surface beneath where the coil will hang. Strip the ends of an old 3.5mm audio cable (cut from a broken pair of headphones) — three wires inside, twist the ground to one coil lead, twist either L or R to the other. Plug into phone, play music. The coil vibrates against the magnet, the cup amplifies it. It sounds tinny but it WORKS. Talk about what just happened: that's how every speaker in the world works, including the ones in their phone. Now they understand sound.
What you'll need
Enameled copper wire (26 AWG)
AmazonNeodymium disc magnets
AmazonPaper cup
FreeOld 3.5mm headphone cable (cut)
From an old/broken pair of headphones
Free
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