Changes

=== Kilogram ===

=== Kilogram ===

The '''kilogram''' (symbol kg) is the unit of [[mass]]. It is defined as an amount of mass equal to that of the standard prototype kilogram kept at the International Bureau of Weights and Measures at Sèvres, France. It is the ''only unit of measure'' based on a physical artifact. This is the same artifact that has provided the definition of grams and kilograms for over a century. It is also the only base SI unit to retain its decimal prefix, ''kilo-'', which comes from the [[Greek]] word for "thousand."  Efforts are presently underway to redefine the kilogram more rigorously than it is defined today.

The '''kilogram''' (symbol kg) is the unit of [[mass]]. It is defined as an amount of mass equal to that of the standard prototype kilogram kept at the International Bureau of Weights and Measures at Sèvres, France. It is the ''only unit of measure'' based on a physical artifact. This is the same artifact that has provided the definition of grams and kilograms for over a century. It is also the only base SI unit to retain its decimal prefix, ''kilo-'', which comes from the [[Greek]] word for "thousand."  Efforts are presently underway to redefine the kilogram without the use of a physical artifact.

=== Ampere ===

=== Ampere ===