Sound Energy : Definitions, Terms, Units and Measurements
Sound Energy is the energy present in a Sound Field. Being similar to other forms of mechanical energy it causes mechanical vibration in any medium it passes through including air and the human eardrum. The SI units of Sound Energy are joules = watt seconds.
Energy : J : = Force x Distance = Work, a quantity equivalent to the capacity of a physical system to do work; the SI unit of energy is the same as the unit of work - the Joule J and is a Scalar quantity.
1 J = 1 N·m = 1 kg·m2/s2 = 1 W·s = 107 ergs
Energy Flux Density : sometimes known as Intensity
Energy Spectral Density : ESD : describes how the energy of a signal or a time series is distributed with frequency.
Sound Energy : W : is the energy present in a sound field.
W = Wo · 10LW/10 J .... the units are Joules = Watt seconds
Total Sound Energy Density : sum of instantaneous potential and kinetic energy densities.
Sound Energy Flux : q : SI units : W/m2 = J s/m2
is the time average product of the in-phase components of the
Instantaneous Sound Pressure and the
Volume Velocity through the surface element considered. Also known as sound power through a surface element.
Sound Energy Flux Density : is the Sound Energy Flux in a specified direction and sense through an area perpendicular to that direction, divided by the area.