Thermal Properties Flashcards
Thermal energy definition
the sum of the microscopic kinetic and potential energies of all the atoms comprising the system under investigation.
Temperature definition
the speed and microscopic kinetic energy of the molecules of a substance
Thermal expansion
atoms vibrating faster due to a substance being heated -> expansion.
Equation for change in length
alphaL0deltaT where alpha is the coefficient of linear expansion and L0 is the original length
Ideal gas model (assumptions)
the particles are so small that the volume of the particles is negligible, the attraction between particles is zero (no potential energy), the particles are in constant random motion (yes kinetic energy), all collisions are elastic (no loss of kinetic energy), the temperature of the gas is proportional to the average kinetic energy of the molecules
Pressure equation
P = F/A where F is the force and A is the area in meters
Ideal gas law
PV = nRT where R is the ideal gas constant, 8.31, n is the number of moles (one mole is 6.02 e 23 particles)
Heat definition
Heat, Q, is a change in thermal energy. It is the quantity of thermal energy transferred from one system to another system.
Conduction definition
heat transfer by physical contact
Convection definition
heat transfer by fluids (liquids AND gases)
Radiation definition
heat transfer due to the absorption of light energy
Rate of heat transfer equation
Q/delT = kAdelT/L where Q is the heat in joules, L is the length of the object, A is the cross-sectional area of the object, delT is the difference between the ends of length L, and k is the thermal conductivity of the object
Thermal conductivity definition
how well heat is conducted through an object
Specific heat definition
the amount of heat required to raise the temperature of 1 kg or a substance by 1 kelvin.
Heat required equation
Q = mcdelT where m is the mass, c is the specific heat, and delT is the difference in temperatures