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Course: Exploratorium > Unit 4
Lesson 3: Turn Light into Sound- Light into sound introduction
- Materials and tools
- Build and test the receiver
- Build the transmitter
- Construct the parallel circuit, put it all together
- What's going on: Turning sound into light
- Engineering challenge
- Turn light into sound: Complete activity guide
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Construct the parallel circuit, put it all together
A detailed demonstration of how to build this project, from beginning to end. Created by Exploratorium.
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- 3:40why is a signal wire shielded when surrounded by a copper wire?(4 votes)
- it is done so that your signal dose not get interrupted(1 vote)
- Why does current produce heat ?(3 votes)
- Because when electric current flows through a circuit there is a certain amount of resistance, i.e. the flow of electrons is partially blocked and some signal strength is lost. As you probably know, when energy in an electric current is lost, it converts to light and/or heat. Another example of this is an old fashioned incandescent lightbulb. When you flick the switch, electricity flows through a special wire which has very high resistance. The high resistance converts current into light and heat, so the bulb lights up. (And gets very hot as well.)(3 votes)
- why did u connect the copper shielding of the mono plug into the circuit as well?(6 votes)
- the mono plug has two wires inside it one of the wires acts as a shield(1 vote)
- How far away can you place the LED light from the solar panel and still transmit the signal effectively?(1 vote)
- That all depends on three things:
1. The strength of your light (from the Light Emitting Diode)
2. The quality of your filtration on the receiving side (how well do you reduce the ambient buzz of lights)
3. The strength of your amplification (how loud you run your speaker.)(4 votes)
- Dear Friends,
does any of you know why are electrical wires cylindrical?(2 votes)- It is easier to make the wire in a cylindrical pattern when creating the wires.
Also, electricity maximizes a round area better than it does another shape.
Source: http://journals.aps.org/pr/abstract/10.1103/PhysRev.176.857(2 votes)
- what are the materials needed?(1 vote)
- At3:23you talk about that there is a leading wire around the signal wire within the cable. But then you connect one of these to plus and the other one to minus in the end? Please explain.(1 vote)
- Does it matter what lead you use or do you have to use certain colour because they each do a diffrent job?(1 vote)
- is this project expensive? its sometimes hard to get my hand on extra cash if its a high price it is was it is but you know...(1 vote)
- I don't think it's that expensive, but I've never tried it before so I don't know. I'm just going to say it's more than cheap, but less than expensive. Just in the middle.(1 vote)
Video transcript
- [Voiceover] First, I drilled the holes in the breadboard, the pine board. And now I'll have to screw in the screws and the washers. So let's put this all together. I'm gonna start by attaching
a red lead on this side and one of the flattened alligator clips. So they all go to the same connection, so we'll tighten them together. And then on the other side, representing the negative
end of the battery, I'll use a black lead and another flattened alligator clip. The black lead is gonna run over here, and it's gonna attach in the same place that our paper clip
switch adapter attaches. So here we go, here's our
paper clip on that side. Oh, I forgot to put in the 470ohm resister and the black lead from the 9-volt battery power connector. So let me get both of those put together. Sometimes in these projects,
you do need three hands. And plug this into here. Okay, now we've got the
negative leads all connected. The light-emitting diode has
a long leg and a short leg, and the long leg should definitely go to the positive red lead from the battery. The battery, I've connected
it to an alligator clip, an optional alligator
clip, to act as a switch. You don't need to do that. You can run it straight
to a stripped wire. And then on this side we'll finish up the positive connections with a paper clip and the positive lead. Okay, so we have our mono phono jack, and we're gonna need to cut one end off and replace it with alligator clips. So I'm gonna take my wire strippers and cut off the outer insulation. Now you might notice this spray of copper wires around the outside. This copper wire wraps all the way around the inner insulated wire,
which is our signal. And by wrapping a
conductor completely around a signal-carrying wire, you can shield it from
outside interference. So this is a very nice system. Now we'll get in here. The inner wire, and now we can crimp those
into our alligator clips. You could solder these to make it a more permanent connnection. Again, three hands helps. Okay. We'll get these all
ready to accept our wire, we'll put the shielded one. I'm twisting the leads so that
they hang together better. And there is a little hole. If I can get it through
the hole, that's nice. Ah, there we go, I got
it through the hole. That makes it wind around
just a little bit more. Okay, so now I will crimp these together. Okay, so now I've made my mini phono plug to alligator clip connector. So let's put it all together. I'm gonna attach the battery. The positive side to the
battery is on the red wires, the negative side is on the black wires. I'm now gonna check my LEDs, so I'll take the LED, the long leg goes to the red positive lead, the short leg goes to
the black negative lead. Now I'll close my switch with
the optional alligator clip, and the light is on, so we have power. I'll disconnect it for the moment. Now I'll turn on my radio
(radio playing) and when I plug in my mini phono plug, it disconnects the speaker on the radio and sends the signal to these two leads. Now this is an A/C signal,
so it doesn't matter which lead I connect to which side. Now I'll connect my detector. So I have my solar cell,
it's also gonna pick up an A/C signal, so it doesn't matter which lead I connect to which
terminal of the solar cell. I'll plug that in to the
amplified speaker input, turn on the amplified speaker, and now I'll light the LED. (radio static playing) There is sound coming over.