I describe an experiment involving the moka Italian coffee pot. The pot is an ingenious device for making coffee that uses the liquid-vapor equation of state of the water and Darcy’s law of linear filtration. The filtration coefficient of coffee is measured and a steam engine model is used to estimate the efficiency of the coffee pot.

Topics
Animal sounds, Isobaric process, Equations of state, Combustion engine, Thermal instruments, Thermodynamic properties, Oceanography, Mechanical instruments, Poromechanics, Laboratories
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© 2007 American Association of Physics Teachers.
2007
American Association of Physics Teachers
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