Waves
Wave Intensity
Energy transmitted per unit area per unit time.
Variables
IW/m²
Intensity
Power per unit area
In SI units: kg/s³
Allowed values: greater than 0
PW
Power
Wave power
In SI units: kg·m²/s³
Allowed values: greater than 0
Am²
Area
Surface area
Allowed values: greater than 0
Derivation
I = P/A by definition.
Your notes
0/5000
Check value
Round inputs run through this page's calculator. Use it to test your own working or a rearranged form. It is a test case, not a real-world example.
- P = 2 W (Power)
- A = 3 m² (Area)
Result: I = 0.66666667 W/m²
Other waves formulas with the same quantities
- Sound Level (Decibels) (Sound Waves) shares Intensity
Where this formula is listed
- Waves formulas, under Wave Properties, alongside Wave Equation, Period and Frequency, Angular Frequency, Wave Number and Wave Speed on String.
- In the waves list it comes after Wave Number and before Intensity-Amplitude Relation.
- Waves formula sheet, one of 37 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Wave Intensity formula?
Wave Intensity is written I = P/A. Energy transmitted per unit area per unit time. It belongs to Waves, under Wave Properties.
What are the units in I = P/A?
In SI units, I is intensity, measured in kg/s³; P is power, measured in kg·m²/s³; A is area, measured in m².
How is the Wave Intensity formula derived?
I = P/A by definition. The result is I = P/A.