Speakers and microphones

These sound-output gadgets are transformed drastically from time they were invented. They exist thanks to humans knowing of power of electromagnetic induction. EM induction is based on the following: when electric conductor moves through magnetic field,the electric current is inducted in him. This is happening because of influence of Lorenz force: this force affects any charged particle in movement and tends to turn it from primary direction of movement. Because electric conductor has a huge number of electrons,Lorenz force affects all of them,and forces them to move directional,which is in fact electric current. That is important when we talk about microphones,because this process is happening there constantly. Our voice moves the membrane which leads to inducting of variable current in electric coil which is attached on membrane. Inside of speaker,there are electric coil on which is attached a membrane of speaker and a permanent magnet. When we let a variable electric current through the coil,the membrane will oscillate in accordance with oscillation of current. Why? Because current in movement inducts magnetic field. Magnetic field of permanent magnet and inducted magnetic field interact,which leads to oscillations of membrane. That is principle of functioning of speaker. Nowadays,we have a huge variety of speakers,and it is very hard to decide which one to buy. My advice: buy a 5.1 system of speakers,because you will have a 3D expirience when you watch some movie or play games on computer. Another advice: buy a speakers with wooden case,the sound which they produce is very deep and more natural than other speakers. I think I mentioned the most important. If you have any questions about these gadgets,mail me or leave a comment.