The document summarizes an experiment investigating the photoacoustic effect. The experiment tested whether different wavelengths of visible light produce sound when hitting a photovoltaic cell connected to a speaker. As hypothesized, all wavelengths produced sound but ultraviolet light produced the loudest sound, having the highest energy. The conclusion was that higher energy light produces greater decibel levels of sound through the photoacoustic effect.

1. The Sound of Light
Lillian Yanagawa
Wade Nakamura
Bryan Silver

2. Photoacoustic Effect
• A G Bell discovered
phenomenon in 1880s.
• Light affects surface tension
producing sound.
• Technological
advancements in the
biomedical imaging field.

3. Hawaii Standards 3
• SC.PS.6.5
• Compare transverse and
longitudinal waves and their
properties
• SC.PS.6.6
• Explain and provide examples of
electromagnetic tradition and
sound using a wave model.

4. Preliminary
Observations:
• Sound and light are forms of energy
• Sound and light both produce waves
• Sound waves are compressional
(longitudinal) waves that require a
medium to travel
• Light waves are transverse waves that
do not require a medium to travel
• Visible Light exists in a larger spectrum
from radio waves to gamma waves

5. Research Question:
• Which wavelength(s) of the
visible spectrum produce(s)
sound?

6. Hypothesis:
• If a photovoltaic cell is connected to
a speaker/amplifier and exposed to
the different spectra of visible light
from infrared to ultraviolet, then
the entire spectrum will produce
sound, but the greatest decibel level
will occur at the ultraviolet end of
the spectrum, because the
ultraviolet end of the spectrum is the
most energetic.

7. Materials:
• Amplifier/speaker Scissors
• Vernier LabQuest D-battery
Microprocessor Alligator clips
• Microphone Prism
• Photovoltaic cell Shade
• Wire cork
lead/connectors
• Y-adapter
• Motor
• Pie plate

8. Procedure:
• In three easy steps
• Assemble apparatus

9. Procedure:
• Obtain readings under
• Red, white, and Black light
• Repeat with prism outside
− IR, red, green, blue, UV

10. Infra Red Light Sound

11. Red Light Sound

12. Green light sound

13. Blue Light Sound

14. Ultra Violet Light Sound

15. White light Sound

16. Conclusion:
• Sound produced at all spectra
of visible light
• Intensity of sound varied by
light wave
• Loudest wave produced by UV
• Hypothesis correct, higher
energy light produces greater
decibels.

17. Extension:
• Using a 100w bulb and colored
filters.
• Use of a prism to separate
sunlight.
• Intensity of light in generating
sound.