Topic 2 Flashcards
(29 cards)
current is
the rate of flow of charge round the circuit
voltage (potential difference) is
the driving force that pushes the current around
resistance is
anything in the circuit which slows the flow down
if you increase the voltage then,
more current will flow
if you increase the resistance then,
less current will flow
potential difference is the energy transferred per unit charge passed
true
1 volt =
1 joule/ coulomb
current is conserved at
a junction
a parallel circuit is one with
branches
current doesn’t get used up or lost,
it is conserved
total current entering junction is equal to
current leaving junction
Voltage (V)=
currrent (I) X resistance (r)
ammeter measures the
current
ammeter must be placed in
series
voltmeter measures the
voltage
voltmeter must be placed in
parallel
fixed resistors graph have
straight diagonal line
filament lamp has
curved upward
diode has
flat below 0 but curved upwards after 0
light up
resistance down
temperature up
resistance down
resistors get hot when
an electric current passes through them
the energy transfer in a resister is due to
electrons colliding with ions in the lattice as they move through it
as heat increases,
resistance increases
