Analyses

At some t ime in every student s life comes the exasperating sensation of frustration in problem solving. Somehow , the answers or the calculations do not come out as expected. Often this outcome arises because of inexperience in the
handling of units.The use of units or dimensions along with the numbers in your calculations requires more attention than you probably have been giving to your computations in the past, but paying attention will help avoid such annoying experiences. The proper use of dimensions in problem solving is not only sound from a logical viewpoint-it will also be helpful in guiding you along an appropriate path of analysis from what is at hand through what has to be done to the final solution.
Dimensions are our basic concepts of measurement such as length, time, mass, temperature, and so on; units are the means of expressing the dimension s, such as feet or centimeters for lengt h, or hours or seconds for time . Units are associated with some quantities you may have previously considered to be dimensionless. A good example is molecular weight , which is really the mass of one substance per mole of that substance. This method of attaching units to all numbers which are not
fundamentally dimensionless has very practical benefits.