Rules of Thumb!

(Strictly Engineering)-
Rules of Thumb
There are the so called rules of thumb in engineering. There are also things called empirical formulas. These things may be called convenient tools, and could be discounted as to their value and usefulness sometimes. But, come to think of it, they are often near to the truth or safe solutions, when used. The often called rules of thumb are actually methods that are used for expediency, but when detailed calculations are made theoretically, the results are near to that one , arrived at using the rule. Similarly, empirical formulas, when conditions are well understood and defined provide very useful solutions.
Written by: Sanoy Suerte, RME/MBM; http://www.linkedin.com/in/sannysuerte