by John Krigger | Jan 20, 2022
(1.5 CEUS) Electricity has become an essential for our civilization. You need to know a little about electricity, how it creates heat, how it operates and controls devices, and how we generate it.
by John Krigger | Jan 20, 2022
(1.5 CEUs) Pressure is a physical principle that describes the difference in density, elevation, temperature, concentration (or some other measurement) between one place and another. Flow and pressure are related to one another. Pressure causes flow, and flow causes...
by John Krigger | Jan 20, 2022
(2.0 CEUs) People need space conditioning systems because the outdoor temperature is different than the temperature that people prefer indoors. This lesson explains basics of how buildings gain and lose heat according to the season.