The model compares pressure-wave amplitudes at a fixed frequency and distance. Increasing amplitude changes the vertical extent of the wave without adding cycles. For a sinusoidal wave in the same medium, intensity is proportional to pressure amplitude squared. Human loudness also depends on frequency, duration, surroundings and the listener, beyond this simple relationship.
Light, sound and electricity · Discover & try
How does wave size relate to sound strength?
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amplitude
The size of a repeated change around its middle value.
intensity
Energy flow per unit area in the physical comparison.
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Pressure amplitude and relative intensity at fixed frequency; no real sound level or hearing test.
What to look for
- Amplitude changes height
- Frequency stays fixed
- Relative intensity follows amplitude squared
Explain what you noticed
Pressure amplitude rises from 2 to 6 units in the same medium. By what factor does this model intensity change?
Keep this idea: Wave amplitude and perceived loudness are related but different quantities.
Follow the sources
- NIH Curriculum Supplement — Hearing, Communication, and Understanding
- NIH / NIDCD — How Is Sound Measured?
- OpenStax, Rice University — Sound Intensity and Sound Level
Source material checked 2026-10-29. Explanations and activities by Nepedia. Source links do not imply endorsement.
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