Units of Measures!

Consistency of Units of Measures! Back to basics.
One of the common source of errors in the solution of a problem in engineering is the making of the model of the problem in a model space. A model is a simplified representation of the actual problem in real life situation. It is almost exact, but not necessarily always. That is why it is called a simplified representation of a confluence.
This involves the making of free body diagrams, and the proper indication of acting forces in such a diagram.

The next common source of problem solution errors, is the an oversight or failure to use consistent units of measure. One has to examine, whether or not units of measures are similarly indicated or not. In a stress-strain problem for example, the stress can be given in Mega Pascals, and the area in mm squared or inches squared, and the unit force being sought after in newtons. Not knowing that a Pascal is in newtons/meter squared and Mega Pascals in Million Pascals can stop dead a novice or even a long time practicing engineer on his tracks to finding the solution to an urgent problem. Important system of units in common use should be made handy for easy and convenient reference always.

I was once working with a student apprentice of mine in analyzing a problem, and I was so surprised to notice that even the basic geometric principle of “alternate angles” being equal and law of sines ,have already been forgotten so easily for so short a time. Basic elements of the practice, may be useful from time to time, so these should be kept handy for possible use in the day to day business of an engineer, an architect, or a technical man for that matter. Not appreciating enough the value of simple things may provide undue inconvenience in a fast paced business environment and career setting.
Written by: Sanoy Suerte, RME /MBM; Http://www.linkedin.com/in/sannysuerte.