In this paper, we discuss two well known definitions of electromagnetic momentum, ρA and \epsilon0[E x B]. We show that the former is preferable to the latter for several reasons which we will discuss. Primarily, we show in detail|and by example|that the usual manipulations used in deriving the expression \epsilon0[E x B] have a serious mathematical flaw. We follow this by presenting a succinct derivation for the former expression. We feel that the fundamental definition of electromagnetic momentum should rely upon the interaction of a single particle with the electromagnetic field. Thus, it contrasts with the definition of momentum as \epsilon0[E x B] which depends upon a (defective) integral over an entire region, usually all space.
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