Fluids
Fluids are matter that flows, liquids and gases both. Four ideas carry the unit. Density is a property of the substance, not the sample. Pressure climbs with depth and depends on density, not on the shape of the container. The fluid pushes up on anything sitting in it, and a comparison of densities decides whether the object floats or sinks. And in moving fluid, a narrower channel speeds the flow while the faster flow drops the pressure.
Equations For every problem in this unit
60 open-ended problems.
Read the question, work it out, then flip the card to compare your reasoning to the worked solution. Mark each card so you can return to the ones that still bite.
Switch to All, work through some cards, and tag them as Got it or Revisit.
Test the unit.
Twenty mixed items pulled from across all 4 topics. Identifies which misconceptions still bite when you cannot see which topic the question came from.