Kilo’s weight in the bal­ance

Weekend Argus (Saturday Edition) - - NEWS -

LON­DON: For those who still have trou­ble con­vert­ing be­tween met­ric and im­pe­rial, take some com­fort. Even em­i­nent sci­en­tists get con­fused over such mat­ters – and are cur­rently ar­gu­ing over the “weight” of a kilo­gram.

Since mea­sure­ments are man-made units, the only ac­cu­rate way to mea­sure a kilo­gram is to com­pare it with one of 40 platinum and irid­ium casts made in France in 1879.

Un­for­tu­nately, each time the cast is han­dled, some atoms come away – mak­ing it slightly lighter. So sci­en­tists are talk­ing about an al­ter­na­tive.

Mea­sure­ments have been changed be­fore. In the 18th cen­tury it took the French seven years to de­cide that a me­tre should be one ten-mil­lionth of the dis­tance from the North Pole to the Equa­tor. – Daily Mail

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