How many wavelengths of #Kr_86# are there in one metre?

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1 Answer
Dwight
Nov 21, 2017

The answer is (4) 1 650 763.73

Explanation:

This question relates to a definition of the meter that was in effect from 1960 until 1986, and stated that one meter was equal to the total length of 1 650 763.73 wavelengths of the orange-red emission line in the electromagnetic spectrum of the krypton-86.

(It has since been replaced by a definition based on the speed of light.)

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