Ch4 Flashcards
description of what happens after the gasoline/air vapor mixture ignites
The gasoline/air vapor _ within the piston chamber, causing it to do _
description of what happens after the gasoline/air vapor mixture ignites
The gasoline/air vapor expands within the piston chamber, causing it to do work
why sun warms us up
During heat radiation, the object absorbs more radiation than it emits, allowing the object to get hotter and hotter
efficiency eqt
hot-cold/hot
In a heat engine, the energy from the so-called “hot reservoir” goes where?
Into the cold reservoir and into doing work.
describes what the temperature of an object measures?
The average thermal energy per particle making up the object.
In the process of convection, once a particle has been warmed up:
it cycles through the _, losing _ but eventually _ to the _and warming up once again.
In the process of convection, once a particle has been warmed up:
it cycles through the system, losing energy but eventually returning to the heat island and warming up once again.
describe Heat death of the universe
The idea that all energy in the universe will ultimately wind up as unusable energy
A heat engine produces work by which of the following?
Heat is converted to _ and the _ is expelled.
A heat engine produces work by which of the following?
Heat is converted to work and the excess heat is expelled.
Natures direction
Tendency of all systems to evolve from _ to more _ states
Tendency of all systems to evolve from improbable to more probable states
heat is
_ in motion
heat is energy in motion
Two objects are defined to be at the same temperature if _
Two objects are defined to be at the same temperature if no net heat flows spontaneously from one to the other
Gallon vs pint of water
Same heat?
Same temp?
Gallon has more heat (internal energy) than a pint, but they are at the same temperature
Difference
Heat is form of energy, temperature is a measurement
Temp Scales
water freeze and boil
F
C
K
Fahrenheit
0: Mixture of ice, salt, and water
32: ice melt
96: human body temp (real 98)
Celsius
0: water freezing
100: water boiling
Kelvin
0: absolute zero= motion stops
1k=1c
273=water freeze
373=water boil
what is absolute zero
Absolute zero= 0K
Impossible to extract heat from atoms (stop moving)
Factors determine how quickly heat is transferred between objects
Temperature difference
Thermal conductivity
Distance
Is it more energy efficient to keep at constant temperature or set it on a variable schedule
If you keep it on constant you will lose more energy when it is too cold or at night when there is a large temperature difference
Specific heat capacity
a measure of the ability of a material to _ and is defined as the _ required to raise the temperature of one gram of that material by 1°C
largest heat capacity?
Specific heat capacity
a measure of the ability of a material to absorb heat and is defined as the quantity of heat required to raise the temperature of one gram of that material by 1°C
large heat capacity?= water
Conduction
The movement of heat by _ atoms or molecules
A chain of collisions occurs, with atoms progressively farther and farther away from the heat source moving_
Conduction
The movement of heat by collisions between vibrating atoms or molecules
A chain of collisions occurs, with atoms progressively farther and farther away from the heat source moving faster and faster as time goes by