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Inside a speaker, an electromagnet is placed in front of a permanent magnet. The permanent magnet is fixed firmly into position whereas the electromagnet is mobile. As pulses of electricity pass through the coil of the electromagnet, the direction of its magnetic field is rapidly changed.peakers come in all shapes and sizes, enabling you to listen to music on your iPod, enjoy a film at the cinema or hear a friendâs voice over the phone.
Answer: Every amplifier (speaker) has an electrical current. When the current is changing, it produces a magnetic field. To make the cone (or panel) of the speaker move, magnets are used to create an opposing magnetic field which creates vibrations. These vibrations are the sound we hear. Speakers often contain large magnets inside of them, as a larger opposing magnetic field creates more vibrations. The larger the magnet, the louder the speaker.