Thermodynamics Flashcards
Conduction
Process by which heat flows from hot to cold without any net movement of the substance
Thermal conductivity
A measure of the ability of material to conduct heat
Convection
Heat transfer by mass motion of a fluid from one region (more dense) to another (less dense)
Forced Convection
Convection created by external forces (a radiator)
Newton’s Law of Cooling
The rate of change of the temperature of an object is proportional to the difference between its own temperature and the ambient temperature (i.e. the temperature of its surroundings).
Radiation
Heat transfer by EM waves without an intervening medium
Stefan’s Law
The thermal energy radiated by a blackbody radiator per second per unit area is proportional to the fourth power of the absolute temperature and is given by
Q=
C*deltaT
Specific Heat Capacity
The amount of energy supplied through heat to raise the temperature of 1kg of a substance by 1K
Molar Heat Capacity
The amount of energy supplied through heat to raise the temperature of a sunstance by 1K (At a constant pressure/volume)
Latent Heat
The amount of energy absorbed or released when a phase change takes place for the substance
Work done=
Force*change in distance
Pressure*change in volume
Density=
m/v
P=
W/t
Internal Energy=
KE+PE
Change in internal energy=
Heat applied to the system - Work done by the system
Adiabatic
No heat transfer in or out of a system
Q=0
Change in Internal energy=-W
Isothermal
No change in temperature
Q=W
Change in internal energy= 0
Isobaric
No change in pressure
P=kQ
Work done=0
Isochoric
No change in volume
Q= change in internal energy
W=0
Cyclic
A process that returns to its original state
Q=W
Change in internal energy=0
Law of increasing disorder
Heat never flows spontaneously from a cold region to a hot one
How do you calculate work done from a heat engine?
W=Q1-Q2
What is the Carnot cycle?
It is a perfect heat engine
What does the area in the cycle graph show?
The useful work done by the engine
