The formula to calculate the sound pressure level in decibels (dB SPL) is:

$\text{dB SPL} = 20 \cdot \log_{10} \left( \frac{P}{P_{\text{ref}}} \right)$

Where:

• $P$ is the sound pressure (in pascals, Pa),
• $P_{\text{ref}}$ is the reference sound pressure, which is typically $20 \, \mu\text{Pa}$ for air (the threshold of hearing).

Given that $P = 20 \, \mu\text{Pa}$ and $P_{\text{ref}} = 20 \, \mu\text{Pa}$, let's calculate the dB SPL.

$\text{dB SPL} = 20 \cdot \log_{10} \left( \frac{20 \, \mu\text{Pa}}{20 \, \mu\text{Pa}} \right) = 20 \cdot \log_{10}(1) = 0 \, \text{dB}$

Thus, the sound pressure level is 0 dB SPL.

Would you like any further details on this calculation or more examples?

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Here are 5 related questions to expand on this topic:

1. What is the relationship between sound pressure and sound intensity?
2. How does the dB SPL scale behave for different pressures?
3. Can the dB SPL level be negative, and what does that mean?
4. How does distance from a sound source affect the dB SPL?
5. What are the typical dB SPL levels for everyday sounds?

Tip: dB SPL is a logarithmic scale, so small changes in pressure can result in large changes in perceived loudness!