Unraveling the Meaning of l' = l + $\alpha$a

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The equation l' = l + αa indicates that α is a dimensionless coefficient close to 1, suggesting it can take values like 2 or 3 but not extremes like 0 or 12352. When calculating l', if l and a are known, α can be approximated based on the context of the problem, typically around 1. This means l' will be slightly adjusted from l by a factor of a scaled by α. Understanding α's range helps in making accurate predictions in calculations involving this equation. The discussion clarifies the significance of "order of unity" in practical applications.
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While reading a physics text, I came across an equation
l' = l + \alpha\,a, where \alpha is the order of unity. What exactly does this phrase mean (ie if I knew l and a, what would \alpha be?)
thanks
 
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Warr said:
While reading a physics text, I came across an equation
l' = l + \alpha\,a, where \alpha is the order of unity. What exactly does this phrase mean (ie if I knew l and a, what would \alpha be?)
thanks

Guess what was written was " is of order unity", no ?

It means that \alpha is a number that is not very far from 1, say 2 or 3 or so. Not 12352.0 and not 0.00002345.
 
Yes, that is exactly what was written.
so if I am doing a calculation based on this statement, what could I give the value of l' to be assuming I knew the precise values of l and a?
 
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