This material may be copied only for noncommercial classroom teaching purposes, and only if this source is clearly cited. Another discrepant event problem is probed, to help students get familiar with the process of science. A plastic bottle with three holes covered with tape is filled with water and capped. Students predict what may happen as the tape is removed from each hole in turn, and hypothesize about the cause of the observed results.
Scientific knowledge is uncertain, tentative, and subject to revision.
Predictions are the expected results of experiments, based on a given hypothesis. 2. suggest valid and discriminating tests to challenge a hypothesis. 3. predict the reasonable alternative outcomes of those tests, depending on whether the hypothesis is correct or not correct. The bottle is then filled with water, and tightly capped. Have a basin and towel close at hand during the demo.