how do earphones work?

by c2
Tags: earphones, work
 P: n/a [?] I need help with my homework. We're supposed to explain how earphones work, using the simplest terms. I know it involves a coil of wire and a magnet and how the magnet vibrates with the sound but i can't quite explain it all myself. Any help would be appreciated. -Thanks
 Sci Advisor P: 1,341 Greetings ! Welcome to PF c2 ! (Oops... I thought you were asking about microphones so I started from one, I now added the earphone part below.) Well, in the simplest form like you asked, the magnet moves at the frequency of the sound waves and as it moves it creates an alternating magnetic field. This amf forces the free electrons in the coil to move back and forth as well which in turn creates an alternating electric field in the coil (and across the electric circuit), much like a generator. In an earphone, the same happens in reverse. An alternating electric field (at the appropriate frequency from a microphone or a recording) forces the electrons in the coil to move back and forth creating an amf round the coil. A magnet inside the coil (that has its own magnetic field) is affected by it and moves back and forth as well. As the magnet does so it creates sound waves of the required frequency in the air. Live long and prosper.
Mentor
P: 21,651
 Originally posted by c2 [?] I need help with my homework. We're supposed to explain how earphones work, using the simplest terms. I know it involves a coil of wire and a magnet and how the magnet vibrates with the sound but i can't quite explain it all myself. Any help would be appreciated. -Thanks
You just did explain it. Sound is a vibration. Coil makes the magnet (attached to the speaker) vibrate. Simple as that.

P: 1

how do earphones work?

 Quote by drag Greetings ! Welcome to PF c2 ! (Oops... I thought you were asking about microphones so I started from one, I now added the earphone part below.) Well, in the simplest form like you asked, the magnet moves at the frequency of the sound waves and as it moves it creates an alternating magnetic field. This amf forces the free electrons in the coil to move back and forth as well which in turn creates an alternating electric field in the coil (and across the electric circuit), much like a generator. In an earphone, the same happens in reverse. An alternating electric field (at the appropriate frequency from a microphone or a recording) forces the electrons in the coil to move back and forth creating an amf round the coil. A magnet inside the coil (that has its own magnetic field) is affected by it and moves back and forth as well. As the magnet does so it creates sound waves of the required frequency in the air. Live long and prosper.
Can you give me an appropriate MLA for this information?

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