May 22, 2014
closed pathway for transfer of energy – complete circuit
source of energy – electrical potential difference/voltage (battery)
flow of electrons that transfer the energy - current
device that uses the energy – load – source of resistance in circuit (light bulb)
a container in which a chemical reaction occurs to release electrical energy
two or more cells connected together
it gives 1.5 J to every coulomb of charge that passes through it
D cell can supply more coulombs of charge – lasts
longer, more power
electric field set up in wire
conduction electrons accelerate to positive terminal
collide with lattice ions and transfer energy
net speed of conduction electrons – very slow – one hour for 1 meter of copper wire
May 22, 2014
rate of flow of electric charge
May 22, 2014
ratio of applied potential difference to current
For a conductor at constant temperature, potential difference is
proportional to current over a wide range of potential differences
the resistance of these materials is constant over a wide range of applied voltages
device whose resistance remains
constant – obeys Ohm’s law
device whose resistance changes
– doesn’t follow Ohm’s law