Unit 2 Test Flashcards
(37 cards)
What are things made up of?
molecules (or other groups of atoms)
Why did the food coloring move faster in hotter temperature water?
Molecules are moving faster than the food coloring molecules spread out faster.
Absolute zero
0 degrees celcius (32 degrees F)
Temperature is…
the average kinetic energy in the molecules of a thing
formula for average
total KE / total molecule = temp
If something is hot
molecules have more speed/ KE
if something is cold
molecules have less speed/ KE
Why do molecules change speed
the speed up when they get energy from other molecules and slow down when they give energy
if a mug is sitting out what will happen?
the molecules in the cup will transfer energy to the molecules in the air until the reach a stable state or equilibrium
when energy transfers it../
an increase of energy in one part of the system and decrease in energy in the other
when two molecules are in contact…
they collie and kinetic energy transfers from the faster moving molecules to the slower moving molecules
which way does thermal energy transfer
hot—-> cold
energy transfer stops when?
energy transfers when equilibrium is reached
explain newtons cradle
when lifting a sphere on one side of the cradle, letting swing and collie with the stationary soheere it transfer the kinetic energy to the last causing it to swing up and back down transfering energy to the other en again, stops becuase of friction
when two things come in contact…
their molecules collide causing a transfer in kinetic energy from the faster moving molecules to the slower moving molecules
energy cannot be created nor destroyed so…
as energy transfers, it increases in one part of the system as it decreases in another part of the system, the total kinetic energy stays the same
the total kinetic energy of an object is…
thermal energy
thermal energy is…
the total kinetic energy of an object
absolute zero is when…
molecules are not moving
greater the mass
higher the thermal energy, lower the temperature.
what determines how much something will change temperature?
the number of the molecules in the object, its temperature (average kinetic energy), and thermal energy (total energy) determines if there will be a temperature change. molecules will continue to transfer kinetic energy until both objects in the system reach equilibrium
for things at the same temperature…
For things at the same temperature, the thing with more molecules has more total kinetic energy (thermal energy) than the thing with fewer molecules.
at equilibrium…
At equilibrium, the average kinetic energy (temperature) of the molecules in the system is the total kinetic energy (thermal energy) evenly divided by the number of molecules in the system.
when a thing loses or gains energy…
the energy gained or lost is divided among all the molecules of the thing
