Definition
The amount of sound energy passing through a unit area each second, typically measured in watts per square meter. Sound intensity describes the physical strength of a sound wave at a specific point and is the objective basis for the perceived loudness of the sound.
Plain English
How much sound energy is hitting a given area every second. The stronger the sound wave, the higher its intensity, and the louder it seems to the ear.
Context Anchor
Seen in discussions of aircraft noise, engine noise, hearing protection, and how sound weakens with distance from its source.
Derivation
From Latin intensus, meaning 'stretched tight' or 'strong.' Sound intensity is literally a measure of how strong the sound energy is as it passes through the air.
Why Pilots Care
Cockpit and engine noise can reach intensities high enough to cause permanent hearing damage over time. Understanding sound intensity is the foundation for choosing the right headset and hearing protection for the flight environment.
Grounding Statement
Near a running aircraft engine, more sound energy reaches your ears each second than it does farther away, so the sound intensity is higher close to the engine.
Intuition Check
Sound intensity does not mean pitch. Pitch is whether a sound seems high or low; sound intensity is how strong the sound energy is at your location.
Example Sentence 1
The sound intensity inside the cockpit during takeoff was high enough that the pilot was glad to be wearing a noise-canceling headset.
Example Sentence 2
High sound intensity near the propeller can make it difficult for ground crew to communicate without hearing protection.