30 terms

Physics pg. 350-351


Terms in this set (...)

What is the origin and meaning of the word "thermodynamics"
movement of heat
Is thermodynamics mainly concerned with microscopic or macroscopic processes
By how much does the volume of gas at 0 degrees C contract for each decrease in temperature of 1 C degree when the pressure is held constant
By how much does the pressure of gas at 0 degrees C decrease for each decrease in temperature of 1 C degree when the volume is held constant
If we assume the gas does not condense to a liquid, what volume is approached for a gas at 0 degrees C cooled by 273 Celsius degree
volume approaches zero
What is the lowest possible temperature on the Celsius scale? On the kelvin scale?
C: -273
K: 0
Is the principal concern in the study of thermodynamics the amount of internal energy in a system or the changes in internal energy in a substance
changes in internal energy
How does the law of the conservation of energy relate to the first law of thermodynamics
first law is a restatement of conservation of energy
What is meant by a system
well defined group of atoms, molecules, objects, or an area
What is the relationship among heat added to a system, change in the system's internal energy, and external work done by the system
heat added equals change in internal energy plus work done
What happens to the internal energy of a system when mechanical work is done on it? What happens to its temperature?
when work is done, both internal energy and temp increase
What condition is necessary for a process to be adiabatic
no heat enters or leaves the system
If work is done on a system, does the internal energy of the system increase or decrease? If work is done by a system, does the internal energy of the system increase or decrease?
on a system- increase
by the system- decrease
How do meteorologists express the first law of thermodynamics
air temp rises as heat is added or pressure increased
What is the adiabatic form of the first law
air temp rises (or falls) as pressure increases (or decreases)- depends on direction
What generally happens to the temperature of rising air? Of sinking air?
rising air- temperature falls
sinking air- temperature rises
What is a temperature inversion
condition wherein upper regions of air are warmer than lower regions
Do adiabatic processes apply only to gases
No, it applies to all fluids
How does the second law of thermodynamics relate to the direction of heat flow
heat never of itself flows from a cold object to a hot object
What three processes occur in every heat engine
gaining heat
converting some to mechanical work
expelling the remainder of heat or changes to lower form
What exactly is thermal pollution
expelled heat that cannot be used to do work
How does the second law relate to heat engines
only some of the work done on an engine operating between two temperatures can be converted to work, with the rest expelled
Why is the condensation part of the cycle in a steam turbine so essential
condensation reduces pressure on the backside of turbine blades, allowing a net force to turn them while water is being recycled
Distinguish between high-quality energy and low-quality energy in terms of organized and disorganized energy. Give an example of each.
high quality- organized energy
low quality- disorganized energy; no work is able to be done
How can the second law be stated with regard to high-quality and lower-quality energy?
high quality energy tends to convert to low quality energy (law of entropy)
With respect to orderly and disorderly states, what do natural systems tend to do? Can a disorderly state ever transform into an orderly state?
Natural state- organized to disorganized
No, disorderly cannot transform into orderly
What is the physicist's term for measure of amount of disorder
Distinguish between the first and second laws of thermodynamics in terms of whether or not exceptions occur.
1st law- no exceptions
2nd law- exceptions
What is the third law of thermodynamics
No system can have its absolute temperature reduced to zero
What is the zeroth law of thermodynamics
2 systems, each on thermal equilibrium with a third system, are in equilibrium with each other