Idea 4
Entropy is closely related to the
2nd law of thermodynamics.
The Second Law of Thermodynamics is unique among laws of physics in that it
Can be states in different ways, tells us what cannot happen, has something to do with the nature of time, and deals with entropy.
Which of these is an example of heat engine?
Electric power plant Jet plane engine Car or Truck engine Earth's Climate System All of the above
The Law of Conservation of Energy tells us "Time's Arrow"
False
Examples of what is not a heat engine?
Hand grenade and Home furnace
If you run a refrigerator in a closed room with the refrigerator door open, the room temperature will
Increase
Name something that is possible according to the second law of thermodynamics
It makes life possible for many life forms. Life forms make highly organized molecules, but this can only happen if we disorganize other molecules (food.)
Which of Newton's Laws are different when time is running backwards?
None
Name something that is not possible according to the second law of thermodynamics.
Total entropy decreasing and the arrow of time going backwards.
Which component(s) must all heat engines possess?
a component at high temperature and a component at low temperature
When we talk about entropy, we are referring to
a numerical attribute of something
Heat engines are important to our everyday lives because they
are used in electric power plants, trucks, and cars.
An electric "heat pump" is used in many homes for cooling during hot weather. Why does this not violate the second law of thermodynamics?
because it consumes electricity
When something becomes more organized, its entropy
becomes smaller
Organisms can only be alive if they:
consume some substance whose entropy can increase
What does the total amount of entropy never do?
decrease
In order for a heat engine to function, there must be a (an):
difference in temperature
Spontaneous heat flow is always from
higher to lower temperature
What does entropy always do?
impossible to say without knowing the details
The entropy of everything in the universe must
never decrease
Is an "evaporative cooler" an example of a refrigerator?
no, it does not use mechanical energy (the fan just moves the air) and it cannot run continuously
Your neighbor Dr. Marty McCrazy has a new invention. He says that it generates 200 horsepower of usable work every minute, and all it needs to run is a quart of room temperature water, and after it is finished, you get half a quart of warm water left over. Is this a project you should invest in?
no, this isn't possible
In order for the entropy of one thing to increase
nothing else need happen
How might a refrigerator be constructed from a heat engine?
run it in reverse
Entropy and disorganization are
strongly related to one another
In order for the entropy of one thing to decrease
the entropy of another thing must increase by an equal or larger amount