Competition Problem 2 English Version

 

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Scoring Rubric:

Recognition that convection is the phenomena that changes between the experiments. (this as opposed to wind, impact at the bottom, stirring while dropping, Vacuum from dropping etc.) 2 points

Some reason offered for convection. Including:

  • density differences,
  • supporting weight of air above,
  • pressure gradient,

    • leading to buoyancy. 1point .

    Recognition that the falling case is missing the convection because:

  • g is the same for all parts of system
  • There is no need to support upper layers while falling so no pressure gradients arise.
  • The entire system is weightless (equally)  (even though this is not true, it is an acceptable way to express it for this judging) so density differences now do not matter.

    • 1 point

    There should be a comparison of oxygen burned. Most of the Oxygen in the first case, and only that around the flame in the last case. The comparison can be distributed through the answer. 1 point

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