proportionality question

[rinsterman12]

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How in the equation, this is a made up equation, E = -1/r does E proptional to -1/r the same thing as saying e proportional to r. I had been told that those are the same statement, but I thought that only applied to exponents, 1/2^2 is the same as saying 2^-2. I do not see how that applies when you a multiplying by a negative.

 

[yummyoatmeal]

Your post is a little difficult to interpret, but here is my interpretation.

In the equation E = - 1/r, we say that E is inversely proportional to r, or that E is directly proportional to 1/r (or r^-1). The negative sign is not considered when speaking of proportionality in this way. If someone told you that E (you wrote lower case e) is proportional to r, then they are wrong.

Edit:
What I said about is how many people speak informally. To be more specific, you would say E is inversely proportional to *negative* r, or that the *magnitude* of E is inversely proportional to r.