19 - Thermal physics Flashcards
Define evaporation
the process by which a liquid becomes a gas at a temperature below its boiling point
Define internal energy
the sum of the random distribution of kinetic energy and potential energy of the atoms or molecules in a system
Define first law of thermodynamics
increase in internal energy = energy supplied by heating + work done on the system
Define isothermal change
a change of a system in which the temperature remains constant
Define thermal energy
energy transferred from one object to another because of a temperature difference
Define thermal equilibrium
conditions when two or more objects have the same temperature so that there is no net flow of energy between them
Define absolute zero
the temperature 0K, at which a system has minimum internal energy
Define thermocouple
a device consisting of wires of two different metals across which an e.m.f is produced when the two junctions of the wires are at different temperature
Define specific heat capacity
the energy required by unit mass per unit temperature change
Define specific latent heat of fusion
amount of heat energy per unit mass needed to convert unit mass of solid to liquid without change in temperature
Define specific latent heat of vaporisation
amount of heat energy per unit mass needed to convert unit mass of liquid to gas without change in temperature
