physical units

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physical units Units used in measuring physical quantities. For example, the kilogram unit of mass is defined as the mass of a specified block of platinum. Other masses are measured by weighing them and comparing them, directly or indirectly, with this. Units are of two types: base units that, like the kilogram, have fundamental definitions; and derived units that are defined in terms of these base units. Various systems of units exist, founded on certain base units. They include Imperial units (foot, pound, second), CGS units (centimetre, gram, second), and MKS units (metre, kilogram, second). For all scientific purposes, SI units have been adopted.

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physical units

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