science C Flashcards
there were some early ideas about ________ described as a substance made of ________ and _______
heat, fire and air
heat is considered a form of ________
energy
heat used to be considered an invisible fluid called _______
caloric
heat energy comes from what?
the movement of particles
temperature
a measurement of the average kinetic energy of the particles in a substance
thermal energy
the total kinetic energy of the particles
describe a solid
particles are attached to each other, very limited in movement, move back and forth in a fixed position, have less kinetic energy than the particles in a liquid or gas. h
describe a liquid
particles are loosely attached to each other, easily slip past each other, takes shape of container
describe a gas
move in all directions, far apart, fill up container
heating a solid…
makes the particles vibrate more energetically and some move farther away from each other.
melting a solid…
particles vibrate even more, bump against each other, some break loose and the solid melts
heating a liquid…
the particles will move more vigorously, move farther apart
boiling a liquid
the particles bump and balance around, and the liquid changes to a gas
kinetic energy
energy of movement ; particles that make up matter have kinetic energy
heat
is the energy that flows from matter at a higher temp to a lower temp
natural sources of thermal energy
sun, geothermal energy, fire, decay
materials that absorb energy …
are dark and dull and are good at absorbing radiant energy
materials that reflect energy …
are shiny and light colored and good at reflecting radiant energy
conductor
material that allows heat energy or electricity to flow easily
insulator
material that does not allow heat energy or electricity to flow easily
4 main points of the particle model of matter
all matter is made up of tiny particles
the particles are always moving
adding heat makes the particles move faster
the particles have space between them
conduction
flow of energy between substances that are in contact
convection
flow of heat energy that involves moving liquid or gas particles
radiation
flow of energy in the form of invisible waves
economic costs
the costs in dollar of using
environmental costs
the negative effects on the environment
societal costs
negative effects on people all together
co generation
technology of producing two or more forms of energy from a single energy generator
describe how a thermostat works
a mercury switch sits on a bimetallic strip. when the strip starts heating up, it thermally expands until it gets so hot that it causes the mercury to slide off of the wires to the furnace causing the furnace to turn off. the bimetallic strip cools off and it thermally contracts until the mercury slides back onto the wires turning the furnace on.
thermal conductivity
ability of a material to transfer heat by conduction
describe the most to least heat loss in a house
most through walls, through roof, then through floor and gaps, and then windows
r- value
number that indicates the ability of an insulating material to stop or limit transfer of heat energy
sustainability
maintaining a resource
what is hydro electric power?
energy generated by water moving through dam
advantage and disadvantage of hydro electric power?
advantage- renewable and not expensive to open
disadvantage - expensive to build and can flood the land and alter the local ecosystems
disadvantages and advantages of fossil fuel use?
advantages - very easy to obtain and transport and are available in large quantities
disadvantages - burning them pollutes the environment by releasing soot+ ashes and gases such as carbon dioxide, carbon monoxide, and etc.
describe active solar heating and passive solar heating
passive- heated directly by suns waves, insulates the buliding
active- heating something mechanically with energy, used to trap solar energy
local and central heating systems
central - method of transferring thermal energy from a single, central source through a network of pipes, ducts and vents
local- method of providing thermal energy for one small area only, ex fireplace
3 energy users?
home, transportation, industry
