how can we convert sound energy to electric energy?

Answer 1

You do this by use of a common household device called a microphone. Sound waves hit a small diaphram within the microphone. This causes it to move with the sound waves. As the diaphram moves, it also moves a coil of wires which is set inside of a permenant magnet. This movement creates a current in the wires by Lenz's Law.

Answer 2

Of course, use a microphone, but the ernergy collected is very small, even for a loud noise.
Somehow, I do not think this is what is in your mind!
Some above said the sound carry very little energy. Not exactly true!
Sound is a pressure variation (whether in air, a fluid or in a solid), usually repetitive. What makes its energy is the pressure differential AND the speed of the variation.
Set yourself in front of a 1000W speaker, and crack it (that is just apply a quick, full amplitude pulse). You wil be projected a few meters away! So sound DOES carry energy.
Capturing the WHOLE sound and converting the whole of it would be nice, but it means you have to be AROUND the source (a sphere). If the sphere can transform, like a microphone, the whole of the pressure variation, then you will have a few bits of energy.
If you succeed, give me the drawings: I'll make it around town, so I could get rid the all noises...
Don't forget, SOUND is just a pressure variation. The speed of the variation makes it "audible". Infra-sounds and ultra-sounds are also sounds, but we don't hear them. They also carry energy.
Weapons of non-lethal technologies are currently being developed using these sounds (check the movie "the 'something' report, with Tom Cruise - can't remember the title). In that film, the police uses sound weapons, pretty efficient (and very close to the real things).

Answer 3

Everybody keeps telling you about devices that do it, but, no one is telling you how they work.

Two ways:

First: Pezio-electric crystals will generate a small charge when vibrated and vice-versa.

Second: Reversable speakers. A speaker works by using a current to generate a magnetic field via an electromagnet. The magnet is attached to the base of a 'drum'. Thus, the vibrating magnet generates a sound. The same thing can be done in reverse. If you talk toward a speaker, it absorbs the sound energy and begins to vibrate. When a magnet moves within a coiled wire, it generates a current. Thus, the sound has been turned into an electronic signal.

Answer 4

well the answer to this is the same answer to "how does the microphone work?" :

sound is just waves moving through air, the microphone has this diaphragm that is very sensitive to the movement of air particles (just like our ears).

there are several techniques to make use of this movement. i'd mention the crystal microphones which, i guess, are the most modern..
when the diaphragm moves, it changes the shape of a crystal which changes its electrical properties. now if this crystal is somehow put in an electric/electronic circuit, it would change the current/volt signal somewhere on the circuit proportionally to the sound.

after that , we're supposed to go amplify this signal , but that's not what we're really talking about :)

there are other types of microphones, you can have a quick view at them at:

Answer 5

use a microphone-like device...

well, not exactly: take a self (loops of conducting material), put a magnet in the middle and attach a big piece of something to it, to retreive the vibrations from the air and channel them to the magnet, and therefore create a vibration in the magnetic field, and finaly an electric current in the self.


however, all microphones don't use that kind of technology. some use components that change their electric resistance to a current that is forced into it... so, in that case, there wouldn't be any energy conversion/creation (you would be consuming electricity and you wouldn't really create any). Depends on the technology you're using.

Answer 6

get a microphone or even a speaker that is electrically connected as a microphone. :)

if you're thinking extracting energy from sound to convert it to something useful electric energy, you'll be dissappointed since sound has very little energy which also explains our ears should be very sensitive.

Answer 7

You do it every time you use a microphone, a telephone. Remember, a small radio alarm clock can be very loud. It does not take many watts. So sound is not a good energy source. There is not a lot of power in loud sounds to convert.

Answer 8

Microphones

Answer 9

Sound waves carry very little energy, so there isn't much point if you are thinking of harnessing energy.

Answer 10

this is what a microphone does.

the sound vibrations move a diaphram that has a soleniod attatched. as the mag in the solenoid moves it uses the inductive effect to push electrons in a coil of wire.