Area.
Patrick, Fri May 05 2017, 10:50AM
Ok simple question.
I see online, and as I was taught that the area of a rectangle is L x W. So 2 x 3 cm should be 6 cm^2 right ?
But I keep seeing 6 cm^-2 ? all over these scientific and technical PDFs Im reading. I dont get it. Why is that negative there !?
Re: Area.
Dr. Slack, Fri May 05 2017, 10:57AM
so post a link to one of these scientific and technical pdfs and let's see the context, my all-seeing-eye can't quite read over your shoulder.
It's correct to use a length exponent of -2, or per area, if what's being reported is 'something per area', like pressure as N/m^2, also written as N.m^-2. Note the change of sign of exponent, and the change between divide and product.
Re:
Area.
Patrick, Fri May 05 2017, 11:04AM
here:
Re: Area.
hen918, Fri May 05 2017, 12:10PM
Yep, Dr slack is correct. another way to write those units is: mW/cm^2.
If you remember your math(s), taking a minus power is the same as the reciprocal (putting 1 over it) to the power without the minus.