The figure below shows measurements of the temperature in a coffee cup over time. The temperature starts out at 87˚C, drops quickly to begin with, and then approaches quite slowly towards the room temperature of 24˚C. The Problem, "P' ", that we are concerned with, is the cooling of the coffee – something of great importance to coffee lovers. Coffee lovers and producers of cups are the potential stakeholders for this problem. As we go along, you will get access to the temperature data and you will create a model that explains how and why the coffee cools.

First, let us think practically about what is going on. Be curious and explore yourself before reading on. When the coffee is very hot, we notice that the cup itself becomes hot. If we hold our hand above the cup, we feel hot air rising from the cup. The colder the coffee gets, the less hot air escapes from the cup. Hence, it seems as if the outflow of heat varies with the temperature of the coffee cup. Also the room temperature seems to matter, less heat escapes in a hot room than in a cold room. Isaac Newton was probably thinking back and forth like this when he formulated his law of cooling. His law states that the heat loss or temperature loss of an object is proportional to the difference between the temperature of the hot object and the temperature of the surroundings.

From the description above, formulate a hypothesis "H" for the cause and effect relationships that lead to cooling, i.e. the structure. Therefore, I prefer to refer to the hypothesis as a structure hypothesis. In SD the hypothesis is often referred to as a dynamic hypothesis, which could erroneously be interpreted as a dynamically changing hypothesis or a hypothesis for the dynamics of the behavior. Make a serious effort to represent the hypothesis in a model where you combine what you have learnt about accumulating and instantaneous cause and effect relationships. You will get more help as you go along. In this quiz, you will get the general comments to each question at the beginning of the next question in line. However, before you get these comments, you are challenged to construct the model by yourself - piece by piece.