🔋college physics i – introduction review

Intensity

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Intensity is the power per unit area carried by a wave, typically measured in watts per square meter ($W/m^2$). It quantifies the energy flow through a given surface area perpendicular to the direction of wave propagation.

5 Must Know Facts For Your Next Test

  1. Intensity is proportional to the square of the amplitude of the wave.
  2. In sound waves, intensity determines the loudness perceived by human ears.
  3. For electromagnetic waves, intensity is related to both electric and magnetic fields.
  4. The inverse square law states that intensity decreases with the square of the distance from the source.
  5. Sound intensity level is measured in decibels (dB), calculated using a logarithmic scale.

Review Questions

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