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Tufts OpenCourseware
Author: Fulcrum Institute Development Team


  • We have investigated heat transfer by convection using liquids and gases. Could we have used solids instead? Why or why not?
  • Air is a better insulator than fiberglass - so why do we insulate the spaces between the inner and outer walls of our homes with fiberglass?
  • Could there be "density-driven" convection in a satellite orbiting the earth? Why or why not?

Note: Challenges like the ones you tackle this week are opportunities to assess your understanding of the science you've worked with and to stimulate and extend your thinking. Give each challenge your best shot, writing your ideas in your journal. Before you look at solutions, note areas where you think your understanding is solid and areas where it is fragile. Jot down questions you have.

In the discussion this week, refer to your experience with the Challenges. You might pose a question or dilemma, comment on an idea that intrigued you, or, create an additional Challenge based on this week's science focus. Use the subject line S3Challenge.