Corrigendum to “Mechanical wave momentum from the first principles” [Wave Motion 68 (2016) 283–290] (S0165212516301408) (10.1016/j.wavemoti.2016.11.005))

In my paper Mechanical wave momentum from the first principles, the axial momentum is represented as a product of the wave mass [Formula presented] and the wave speed [Formula presented]. The former is introduced as the exceed of the mass density (per unit length) in the wave, [Formula presented], over that ahead of the wave, [Formula presented] It should be noted that this relation is valid not only for mechanical waves but for electromagnetic waves too (that is, it reduces to the known expression for the axial momentum of the latter). Indeed, in an application to electromagnetic waves, we may consider [Formula presented] as the rest mass. Since it is absent, the wave mass becomes where [Formula presented] is the energy density and [Formula presented] is the speed of light. The momentum density follows as [Formula presented] as it should. Of course, this coincidence is not accidental. The fact is that the considerations resulting in the expression (1) in the above paper are true for electromagnetic waves too. The author regrets that he did not note this fact at once.