science: ch 3

forces & energy

mass

the measure of the amount of matter in an object

volume

the amount of space that a substance or object occupies

density

the amount of mass per unit of volume

formula of density

density = mass/volume

conduction

the transfer of thermal energy through a material by direct contact

convection

the rising and falling of liquids and gases due to differences in density

radiation

energy that comes from a source and travels through space

dissipation

the process in which energy spreads out and becomes less useful

evaporation

the change of state from liquid to gas

convection current

the movement around a heated liquid or gas

heat

the total thermal energy of particles in an object

temperature

the average energy of particles

joules

unit of heat

law of conservation

states that energy can’t be created or destroyed, only changed or transferred

dissipation

a process in which energy spreads out and becomes less useful

best emitters/absorbers of radiation

dull, black, large surface area

poor emitters/absorbers of radiation

shiny, white or silver, small surface area