Why is the squared meters negative?

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In energy auditing, the notation W·m-2 represents Watts per square meter, with the negative exponent indicating division rather than a separate measurement. The dot between W and m signifies multiplication, clarifying that W·m-2 is equivalent to W/m2. This notation can be confusing, but it is a standard way of expressing power density in various energy standards. Users in the discussion confirm that while the notation may seem unusual, it ultimately conveys the same information. Understanding this can help avoid misunderstandings in energy auditing practices.
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Hello,
I work in energy auditing. I noticed a lot of the standards I am given for lighting, etc are in Watts per negative square meter: W·m-2.

Does anyone know what this means? Why isn't it just in W·m2 ?
 
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##a^{-n}## means the same as ##1/a^n##

Anything raised to negative power is the same as a fraction with the thing being in the denominator.

So what does ##Wm^{-2}## mean?
 
R_Ham said:
Hello,
I work in energy auditing. I noticed a lot of the standards I am given for lighting, etc are in Watts per negative square meter: W·m-2.

Does anyone know what this means? Why isn't it just in W·m2 ?
The dot between the w and the m is times, not divided by. I'm not sure why you would write it that way, but W·m-2 = W/m2
 
Yes, this all makes sense now. Can't believe I didn't realize that one -_- . I don't know why, but the standards are just always written like that W·m-2.
 

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