physics -electric circuits cp10 p2 Flashcards
what is potential difference
-Measured in volts
-supplies the push
to make charge move
around a circuit and gives
it energy.
-Supplied by batteries or a
power supply
current
-Measured in Amps
- a flow of electrons
(CHARGE) around the
circuit.
- charge carries ENERGY.
-It will only move if there is a potential difference.
-If the potential
difference increases so
does the current.
charge
- Measured in Coulombs
-We can find out the amount of charge flowing passed a point
resistance
-Measured in Ohms, Ω.
-Anything which slows
down the flow of charge.
- Usually the positive metal
ions.
factors which effect resistance
-Longer wires have more
resistance: More ions for
the charges to collide with
-Thicker wires have less
resistance: More pathways
to get through
-Hotter wires have more
resistance: Ions vibrate
more making it harder for charges to move by.
series circuit rules
-Since there is only one
loop, the current in the
SAME size at all points in the circuit.
-It is measured with an
AMMETER in SERIES.
-The potential Difference
of the battery is SHARED
between the bulbs.
- If each bulb has the SAME
RESISTANCE, they will all get an EQUAL share.
-Resistance is anything which tries to slow down the movement of charge.
-Adding more bulbs or resistors in series increases the
overall resistance.
- To find the total just ADD
the individual resistances. - 3 bulbs would have more
resistance than 1 bulb, so
they come on dimmer
since less current can flow
parallel circuit rules
-The current splits up and
follows different paths in a
parallel circuit
- if you add the current in
each path it will be the
current from the battery.
-It is measured with an
AMMETER in SERIES.
-Each pathway receives the
full battery potential
difference, so
bulbs appear brighter in parallel circuits.
-Resistance is anything
which tries to slow down
the movement of charge.
-Adding more parallel
pathways lowers the
overall resistance of the circuit.
-3 bulbs in parallel would
have less resistance than 1 bulb