Which unit is commonly used to measure sound intensity?

The unit commonly used to measure sound intensity is the decibel. Decibels are a logarithmic unit that quantifies the intensity of sound based on a ratio relative to a reference level. This is particularly useful because sound intensity can span a vast range of values, and the logarithmic scale allows for a more manageable representation of this range. A sound that is 10 decibels is perceived as ten times more intense than a sound at 0 decibels; thus, it captures the human perception of sound intensity effectively.

Other units mentioned have their specific applications but do not accurately measure sound intensity. Pascals are used to measure pressure, not sound intensity. Watts are units of power and may relate to sound output in terms of speakers and amplification but not directly to sound intensity itself. Volts measure electrical potential and are also not applicable to the measurement of sound intensity. Therefore, decibels are the standard measurement in the context of sound, making it the correct choice.