This very simple to perform demo can be made very memorable by ensuring the students see it as a discrepant event. Students are expecting to see a free fall but instead see a low terminal velocity with no obvious source of friction.
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Teacher Demo: Osmosis Across a Semi-permeable Membrane
Categories: Teacher Demonstration
Osmosis, the movement of a solvent (usually water) across a semi-permeable membrane from an area of higher solvent concentration to an area of lower solvent concentration, is key in the maintenance... read more
Teacher Demo/Student Activity: Disappearing Volume
Categories: Lab/Student Activity, Teacher Demonstration
In this activity, student mix a given quantity of salt with a fixed volume of water. Mass and volume measurements are made before and after mixing to determine if these quantities change. Students... read more
Teacher Demo: The Nose vs. the Wrecking Ball
Categories: Teacher Demonstration
A pendulum is constructed from a 1.0-kg mass suspended from the ceiling, with a length of strong string long enough so that, when pulled about 40o from the vertical, the mass comes to nose level. The... read more