CAST Interdisciplinary Activities using Computational Science

The Flow Problem Separatory funnel 30 ml graduated burette Graduated flask Rings, clamps and valves

Flow Applications A lake or pond, fed by one river or stream, and drained by another An individual cell's water balance, whether it is a plant cell trying to maintain turgor, or a protist trying to pump water out to counter osmotic pressure A specific organ or cavity's normal range of hydrostatic pressure (e.g., urine in a bladder, or cerebrospinal fluid in a mammalian dorsal cavity) Kinetics, relative reaction rates, and dynamic equilibrium in chemical reactions Nuclear binding energy, fed by particle bombardment and drained by radioactive decay How will the time needed to fill your bathtub be affected by an ill-fitting drain stopper? How long will it take you to go broke if you spend more than you earn? (and pay 18% extra for everything as well)

Fill it up Suppose you started with 5 mL of liquid in the burette and a full separatory funnel. If the bottom valve were closed and the top valve were opened, the burette would begin to fill up. If you recorded the volume of liquid in the burette every minute and plotted your data points, which graph would you expect to see?

Empty it Suppose you now have a full burette. If the top valve were closed and the bottom valve were opened, the burette would begin to empty. If you recorded the volume of liquid in the burette every minute and plotted your data points, which graph would you expect to see?

Model It Find a math model for the inflow rate Find a math model for the outflow rate Use the models to determine the answer to this problem: Describe what will happen to the liquid in the burette if you start with 5 mL of liquid and open both the inflow and outflow valves to the same settings used for the initial data collections.

Inflow Data Burette Vol (mL) Elapsed Time (s)

Outflow Data Burette Vol (mL) Elapsed Time (s)

Related Topics Flow Models Pollutant Levels in a Lake Population Growth Models SR.xls SR.xls Modeling Oscillatory Systems Excelet Tutorial