Thermodynamics (E1) Flashcards
Thermal equilibrium
When two objects in direct contact have unchanging macroscopic properties and share the same temperature
Thermometer
An object whose macroscopic property measurably changes in response to temperature
Constant volume gas filled thermometers
Based on ideal gas law
-As temperature increases, pressure will increase
Liquid filled thermometers
Based on expansion or contraction of a liquid with increases or decrease in temperature
-usually ethanol or mercury
Thermistor
Measures temperature based on resistance to flow of electricity
-higher temperature leads to decreased resistance to flow
Ex. Esophageal stethoscope
Infrared sensor
Measures difference in infrared light emitted by object
Thermal expansion
Two strips of metal expand at different rates per degree temperature change
Heat
Energy in transit from one object to another due to a difference in temperature between the objects
Ways to increase the temperature of an object
- Another object with higher temp (conduction and convection)
- Mechanical work on the object
- Radiate the object
Conduction
Transfer of heat from one object to another when the objects come in direct contact with one another
Rate of heat transfer
Negative sign because heat flows from hotter to colder
-increased heat transfer with increased contact area and or increased temperature difference
Convection
Due to bulk movement of substances of different temperature
Ex. Air flow in OR, lava lamp, boiling water
Electromagnetic wave
Wave consisting of electric and magnetic components that travels through space and carries energy
Radiation
As temperature increases:
-atoma vibrate faster
-range of frequency widens
-intensity of vibrations increase
Body temperature
-maintain tight temperature control
-anesthesia alters the temperature set points
