2.3 Thermodynamics Flashcards
What is 0°C in Kelvin?
°C + 273.15
What is the equation to work out °C from °F?
(5/9°F)-32
What is the equation to work out degrees F from C?
(9/5°C)+32
At what temperature does mercury freeze?
-34°C
What is the purpose of a Wheatstone Bridge circuit?
It is a circuit that changes resistance in response to a change in temperature.
What are the common metals used in a Thermocouple?
Copper and Constantan
What is 1 Calorie in Joules?
(Calorie - Amount of heat needed to raise temperature of 1kg of water by 1 degree C)
4186J
What is 1 BTU in Joules?
(BTU - Amount of heat needed to raise temperature of 1lb of water by 1 degree F)
1055J (0.252 Calorie)
What is the formula to calculate the heat capacity?
Q = mC Δ T
Q = Heat gained or lost
m = Mass
C = Specific heat of substance
T = Temperature
What is the formula for latent heat?
Q = mL
M = Mass
L = Specific latency
What are the three types of heat transfer?
Conduction
Convection
Radiation
What is the temperature at which Water has the greatest density?
4°C
What is Entropy?
A quantitative measure of the amount of thermal energy not available to do work for a closed system. It is the unavailable energy.
How many laws are there in thermodynamics?
Four
What is the First law?
The total increase in the energy of a system is equal to the increase in thermal energy plus the work done on the system.
What is the Second law?
Heat energy cannot be transferred from an object at a lower temperature to an object at a higher temperature without the addition of energy.
What is an Adiabatic process?
One with no heat transfer into or out of a system.
What is an Isochoric process?
It is a constant volume process.
What is an Isobaric process?
It is a constant pressure process.
What is an Isothermal process?
It is a constant temperature process.
What is Enthalpy?
It is the amount of energy in a gas capable of doing work.
It is a combination of internal energy, pressure and volume due to whenever a gas is heated.
What is an Isentropic process?
It is a constant entropy process. It is a reversible process due to no energy dissipating as heat.
What is Boyle’s law?
The Volume of a given mass of gas at a constant temperature is inversely proportional to pressure.
PV = Constant
P1V1 = P2V2
What is Avogadro’s law?
It states that equal volumes of all gases, at the same temperature and pressure, have the same number of molecules.
