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Analyzing Temperature Graphs

During this course, you use your temperature probes to generate a number of graphs showing the change of temperature with time. Perhaps you’ve noticed patterns in the graph lines (curves) generated. Take some time to become familiar with the following 7 common patterns.

As you analyze the graphs you generate in the coming weeks, you can describe them by referring to these 7 patterns of temperature change. You’ll be talking about the direction of temperature change (decreasing, constant, or increasing) as well as the rate of change (increasing or decreasing).

Temperature decreasing

A temperature over time graph for temperature that is decreasing looks like one of the three illustrations below. The temperature, which is on the vertical axis, continues to get lower as time (on the horizontal axis) goes on.

Temp decreasing                             Temp decreasing                     Temp decreasing

at constant rate                                  at increasing rate                      at decreasing rate

No temperature change

A temperature over time graph for constant temperature looks like the illustration below. The temperature is the same the whole time that is monitored.

Temperature increasing

A temperature over time graph for temperature that is increasing looks like one of the three illustrations below. The temperature, continues to get higher as time goes on.

Same pattern, different rate

The pattern of these two curves is the same, what is the difference between them? What everyday events might each curve represent? In your journal, generate an example for each curve.


Complex graphs

You’ll find that many graphs are complex, and may include more than one of the 7 patterns of temperature change. You can identify different patterns within the curve, and use them to tell the story of how the temperature changed over time.

The temperature in the kitchen in the morning was constant - a chilly 17°C. I turned up the heat and the temperature increased, rate decreasing, until it reached 21°C. The temperature was constant at 21°C. I left the room, and when I came back I found the back door open and the temperature had decreased, rate decreasing, to 15°C.