How to make a loudspeaker

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A two-minute video showing you how to make a speaker from wire, a cup and a magnet.

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WHAT YOU NEED: A music source with a speaker jack cable, insulated wire and wire cutters, sandpaper, crocodile clips, plastic cup, pen and pencil and a neodymium magnet. Neodymium magnets are very strong so you'll need an adult to help you.
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STEP 1 - COIL WIRE: Put the spool of wire on a pen. Place this between your knees and unspool the wire while wrapping it around a few pencils to make a coil.
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STEP 2 - TAPE TO CUP: Slide the coil off the pencils and bunch it together...
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... and stick it on the base of your cup.
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STEP 3 - CONNECT: Sand the spare ends of the wire, and attach each end to a crocodile clip. Then attach one clip to the base of the audio cable jack, and the other end to the tip.
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STEP 4 - ADD MAGNET AND PLAY: Take the magnet and hold firmly on top of the copper coil.
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Press 'play' on the music source. You should hear music! The electric current runs through the coil of wire, creating a magnetic field which repels and attracts the magnet as the current changes direction rapidly. This vibrates the cup, making sound!

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