Energy Study Guide
-cause for warming, and change of phase
(Enabled particles of a substance to move farther apart until the attraction of the particles for each other became too weak to hold them together)
2. When the temperature of an object is changed
2. Energy can be cause change by flowing or transferring from one system to another
3. Energy stays the same (maintains identity) after being transferred
-It can be transferred from place to place, but can’t touch it or measure its mass.
-Energy transformation also sometimes seems like the energy is changing rather than the physical system that gains or loses it. (even though info is moved from place to place, nothing about the info changes)
phase energy (Eph)
chemical energy (Ech)
-The quantity of thermal energy stored by a collection of particles is related to their mass and velocity. (you would rather catch barehanded baseballs thrown by instructor than one by a major league pitcher) (it would hurt to be pelted by golf balls, but not by ping pong balls)
-Attractions result in decrease of energy of a system of particles.
-As particles become more tightly bound, their phase energy is lowered.
-Solids possess lowest phase energy, and liquids possess more because the particles move freer. Gas possesses greatest amount because particles have completely broken free of each other.
-These attractions are chemical bonds because they are directed between specific atomsin the molecule.
-Energy is transferred from the hotter object to a colder one.
-If all the molecules have the same mass, then the hotter ones are moving faster than the colder ones.
-A light bulb filament can be heated to the point that it glows and this is the emission of photons that carry energy away from the filament.
2. These particles exert long-range attractions and short-range repulsions on one another. Attractions bring about a reduction in the energy state (Eph ) of the system; repulsions bring about an increase in the energy.
3. A hotter sample is one whose molecules are moving (on average) faster than the molecules in a colder sample.