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Method:
1. Start the datalogging software.
2. Switch on the heat source.
3. Allow the experiment to run for 30 minutes.
4. When fi nished, save or print the results.
Hint: The length of time required for the experiment depends on the amount of soil used.
Results:
What do the results show?
Are the results a surprise?
How does the density of the soil relate to the results?
What might happen to the results if you kept heating the samples?
Going further:
Why is soil temperature such an important issue in plant growth?
Try switching off the heat source and log how quickly the soil cools down. What might this show?
How might you show heat fl owing through the soil using three temperature sensors? What does this show?
How is soil temperature used in heat pumps that heat houses?
What environmental impact does soil temperature have on the
earth and its eco-systems?
What additional factors might you investigate?
What about the difference between wet and dry soils?
How might you investigate soil density and the relationship with
temperature absorbtion?
Biology