Mass and weight are often confused, especially in the [[US Customary System]] of units or any other system of ancient or medieval origin. In such systems, mass and weight are regarded as fundamentally the same. But weight ''can'' change with altitude or even with latitude.
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Mass and weight are often confused, especially in the [[US customary system]] of units or any other system of ancient or medieval origin. In such systems, mass and weight are regarded as fundamentally the same. But weight ''can'' change with altitude or even with latitude.
Weight and mass are related in the following manner:
Weight and mass are related in the following manner: