There is a bar of platinum iridium alloy near pairs with two marks exactly one meter apart. Why is is kept in,

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There is a bar of platinum iridium alloy near pairs with two marks exactly one meter apart. Why is is kept in,

a temperture controled case? This is for my homework and so far I had no chance of finding the answer...

2007-10-11 17:09:47 · 2 answers · asked by Remmy T. 2 in Science & Mathematics ➔ Physics

2 answers

Because from 1889 to 1960 this piece of metal was the standard for the metre when kept at 0 degrees Celsius. Any other temperature would result in the length changing as metals expand and contract according to their temperature.

Read all about it at Wikipedia...

2007-10-11 17:36:47 · answer #1 · answered by AJ B 2 · 0⤊ 0⤋

Like most material, it expands and contracts with temperature.

2007-10-11 17:18:43 · answer #2 · answered by Frst Grade Rocks! Ω 7 · 0⤊ 0⤋