Energy Flashcards
what is energy
the capacity to do work, move matter, make things happen
what is internal energy
the sum of all the energy types in a system
what is work
energy taken away or added to a system
when work is done on a system, is energy transferred in or out?
in
when work is done by a system, is energy transferred in or out>
out
give four types of potential energy
chemical, nuclear, stored mechanical, gravitational
give five types of kinetic energy
radiant, thermal, electrical, sound, motion
give the 1st law of thermodynamics
- in a system of constant mass, the energy involved in physical/chemical change is not created nor destroyed but changed from one form to another
give the 2nd law of thermodynamics
energy changes from a useful concentrated form to a less useful and less concentrated form
give the 3rd law of thermodynamics
the state of absolute zero- heat is vibrational motion of particles and all motion ceases at absolute zero
what is 0 Kelvin in celsius
-273C
what is entropy
measure of the unavailable energy in a closed thermodynamic system/ measure of its disorder
what is the name of the process that converts hydrogen to helium in the sun’s core
nucleosynthesis
what type of reactions occur in the core of the sun
thermonuclear reactions
what process converts matter to energy
fusion
why is the sun’s luminosity so great
enormous amount of fusion which releases a tiny amount of energy each time
how much of the sun’s luminosity does the earth receive
2 billionths
what occurs in the radiative zone
short energy waves are converted to longer waves
why is the sun an almost perfect blackbody radiator
it absorbs all light that strikes it and doesnt reflect any
name a gas in the atmosphere that absorbs energetic and harmful radiation
ozone
give four sources of terrestrial energy
radiogenic heat (breakdown and decay of radioactive elements), accretionary heat (collisions of particles to and from the earth), tidal heating (internal friction from the distortion of the planet, core formation
at what rate does energy come into the earth system
174000 TW
at what rate do humans use energy
10TW
name two ways that energy leaves the earth system
reflection (albedo)
degradation (lost as heat, longer wavelengths)
