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Introduction to Physics — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsIntroduction to Physics2 Marks
Question
The metre is defined as the distance travelled by light in $\frac{1}{299,792,458}$ second. Why didn't people choose some 1 easier number such as $\frac{1}{300,000,000}$ second? Why not 1 second?
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Answer

Until 1960, meter was defined as the distance between two lines on a specific bar of platinum iridium alloy stored under controlled condition. Because of its limited accuracy, it was abandoned by scientist. From the above scale speed of light was 299792458m/ s and not $300000000 ~ms^{-1}$. They needed something which could give them more accurate results in different places and at different times. Thus, in 1983, they adopted distance travelled by light in $\frac{1}{\text{c}}\text{s}.$

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