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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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Light into sound introduction
Turn sound into light and then back again with a few simple materials. Created by Exploratorium.
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Keep watching the videos in this series! Check the next video especially: the "materials and tools".(3 votes)
In the example about the Doppler effect, would it be the case in an experiment such as this,...if the transmitter was rushing towards the receiver, would the pitch of the sound be higher? Is this how we can tell the relative speed and trajectory of stars?(4 votes)- I wish I could say, "yes." Notice that the radio is silent, and0:23, when the red light is blocked. The white light, from the rest of the room was still reaching the receiver. This indicates that the receiver, in the video was selective to a specific frequency of red light. Changing the relative velocity (by millions of miles per hour) of the LED/receiver would likely change the light frequency and make the radio silent. The video demonstrated an AM, amplitude modulation, radio concept.(1 vote)
This doesn't really turns light into sound, right? This just uses light power to supply electrically a sound producing object.(1 vote)- Isn't this a Physics video (energy transfer, circuits, etc)(2 votes)
- What are some practical uses of this phenomenon?(1 vote)
- This network can be used to make a motion-detector or alarm. Perhaps like the clapper (a noise activated light switch, one could use this switch, by waving a hand near the sensor. This device would be great in a garage; when a car approaches the wall and breaks a light beam, the garage radio becomes silent and the vehicle operator knows to stop/park.(2 votes)
- I know this project was posted 4 years ago, so I hope someone can answer my question... We have put the circuit together exactly as instructed in the videos and PDF guide. The LED lights when attaching the battery, however, when attaching the sound source, the LED turns off. Any tips on why this occurs and what we may be doing incorrect ?(1 vote)
- The receiving device (probably a photodiode) has to be polarized too - but I don't see a second battery...(1 vote)
That's impressive work there. Does this mean that the LED's lumosity is fluctuating ever so slightly and being received and interpreted by the receiver? Is it possible with higher frequencies of colored LED's such as green or blue? What kind, if any signal degredation might you get from the LED transmission of the signal?(1 vote)- When the guy was playing the light to sound in sounded like" a living catapult oh yeah!! Life is a living catapult"(1 vote)
This should go in tips and thanks I think 😸(1 vote)
- your video is great but some phones could make vary fast video it should be possible to film light and turn it into sound with a app like your device does it would be funny to have a app like that on my galaxy s 5 is it possible to do that?(1 vote)
0:23Video transcript
- [Voiceover] We're gonna
turn sound into light and then turn the light
back into sound again. (music plays from radio) (music stops) (music plays from radio) (music stops) (music plays)