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Leaky Bucket - Set Up

This exercise has two parts: a model formulation and calibration phase and a model validation or test phase. In the first, students create a model in addition to that based on Torricelli's Law and choose the placement and shape and sizes of holes in buckets to parameterize the models. In the second, an ``Evil Genius'' creates buckets with holes for students to test their models against.

The following materials are needed:

  1. 1-quart plastic jugs such as those containing milk or juice for use as the leaky buckets
  2. Drill and bits to create circular holes
  3. Scapels for cutting non-circular holes
  4. Stop watches
  5. Graduated cylinders for volume measurements
  6. Plastic dish washing tubs for water if a large sink is not available
  7. Ring stands and plates for elevating the buckets
It is up to the students to ensure that they have plans to measure all the parameters needed in their models. This may involve different levels of ingenuity, flexibility, and special equipment from the instructors, depending on the models used.

The Evil Genius will play by a few rules to ensure that unreasonable test buckets are not created. For example, if E.G. wishes to cut more than one hole, he should cut the holes at the same vertical level. In particular, similar plastic jugs will be used. Holes on more than one level will not be used. Otherwise, shape, size, and number of holes will be freely created.

This exercise can be tuned for more or less difficulty depending on instructors' aims and students' abilities. For example:

Our students were easily able to suspend iron filings colloidally in the fluid and examine the behavior of the leaky bucket in a rapidly-rotating magnetic field by the end of the lab.


next up previous
Next: Leaky Bucket - Student Up: Leaky-Bucket Experiment Previous: Leaky-Bucket Experiment
James Powell
2000-07-30