describe matter using the kinetic particle model
the kinetic particle model describes matter as consisting of particles in constant motion, except at absolute zero
do all substances have internal energy
all substances have internal energy due to the motion and separation of their particles
temperature
temperature is the measure of the average kinetic energy of particles in a system
how does thermal equilibrium occur
two systems in contact transfer energy between particles so that eventually the systems reach the same temperature; they are in thermal equilibrium
capacity to do work
a system with thermal energy has the capacity to do mechanical work; when work is done, the internal energy of the system changes
mechanical work
to apply force over a distance
change in internal energy of a system =?
because energy is conserved, the change in internal energy of a system is equal to the energy added by
heating, or removed by cooling, plus work done on/by the system
efficiency formula:
efficiency = energy output / energy input * 100%
forms of heat transfer
heat transfer occurs between and within systems via conduction, convection, and/or radiation