Let K be a local field (e.g., a
p-adic or p-series field) and n a positive integer. Let K′ be the unique (up to
isomorphism) unramified extension of K. It is shown that the natural (modular)
norm of K′ is the n-th power of the usual (l∞) vector space norm of K′ when K′ is
viewed as an n-dimensional vector space over K. Further, the two distinct
descriptions of the dual of K′ (which is isomorphic to K′) that arise from
the field model and vector space model are isomorphic under a K-linear
isomorphism of K′ as a vector space over K, and the isomorphism is norm
preserving.