Energy Density and Power of a Wave.
I. The average energy density (energy per unit volume) of a mechanical wave is 1/2 ρ ω² A².
II. Energy density is directly proportional to the square of the amplitude and the square of the frequency.
III. The power transmitted by a wave is the product of energy density and wave velocity (P = u ⋅ v ⋅ Area).
IV. Power transmitted on a string is independent of tension.
V. A wave of constant amplitude transports energy at a constant rate.
