Assignment 1
Rules to Balance by


In this assignment, you will be given a quick overview of the rules of materials flow balances in a lecture style of questions and answers. Once you grasp these rules and they seem to be common sense to you, you will have completed this assignment.


So, what are the rules of materials flow balances? The five rules to materials balances that I have devised follow:

  1. Elements and widgets can neither be created nor destroyed
  2. What goes in must come out (ultimately)
  3. Environmental releases occur because 100% efficiency is impossible
  4. Industries are dynamic so bulk purchases of raw materials and stockpiling of products and byproducts will occur
  5. Compounds will compound the materials flow balance process, because of reduction of compounds to their elemental forms or the formation of compounds from elements.

Relative to the Wonderful World of Widgets, these rules can be translated as follows:

  1. Widgets cannot be created or destroyed. They must go somewhere, even in pieces.
  2. Widgets that come in, must ultimately go out. the unplated widgets come from the manufacturer and go back to the manufacturer, with broken widgets or widgets which evaluated for QA/QC or widgets which fail QA/QC going to a scrap metal recycler.
  3. The amount of widgets that are received from the manufacturer will not equal the number of widgets that go back to the manufacturer because of breakage, and QA/QC evaluations, and other such xxx which result in environmental releases.
  4. Bulk purchases and stockpiling of products do occur, but at the Wonderful World of Widgets, the raw unplated widgets received by the manufacturer go back to the manufacturer so bulk purchases and stockpiling will not affect the materials flow balance.
  5. Widgets are not compounds. Widgets are tangible articles which cannot be reduced or formed, and thus the materials flow balance will not be affected by this rule.

Once these rules seem sensible to you, you will have completed this assignment.

Go on to Assignment 2
Go back to Course Beginning