Physical formula

1. Sep 13, 2009

thedy

I know,that my question is bizarre,but i m interesting for answer.

To create formula,i mean,that scientist makes experiment and formula is result of it.And I have sometimes problem to understand,what physical formula means.

For example:Average speed is simple to make scheme.Just speed divide by time nad that s it.But others are more complicated.
Example:electric resistance is:R=specific electrical resistance·length/cross section area.

I understand it but,why is not like that:R=specific electrical resistance+length−cross section area.I know,that is like calculate apples with pears,but if length will be longer,R will be higher,and if cross section area will be more extensive,R will be lower.Mathematically,it is very similar.

So,and my terminal and main question is,if the creating of formula is concern of agreement.That means, a few scientists will meet,and they will make a decision about formulas.

Thanks a lot,i know it s stupid question,but i would like to know it.

2. Sep 13, 2009

dx

Scientists don't 'meet and make a decision' about formulas, nor are formulas derived directly from experiments. The construction of scientific theories is a much more subtle process, and there is no general procedure that one follows. It is a creative process, building upon principles already established, intuition, philosophical prejudices etc. Basically, it is a very subtle type of guesswork. If it disagrees with experiment, it is wrong. If you're interested in this, I recommend very highly the following set of popular lectures by Richard Feynman: http://research.microsoft.com/apps/tools/tuva/.

3. Sep 14, 2009

thedy

Thanks for a tip.I will check it.