Y11 Mock Electricity Flashcards
what is needed for electrical charge to flow through a closed circuit
for electrical charge to flow through a closed ciricit the circuit must include a source of potential difference
what is electrical current
a flow of electrical charge. the size of the electric current is the rate of flow of electrical charge
what does the current through a component depend on
the resistance of the component and the potential difference
what is potential difference
the push of electrical charge
what is resistance
slows down the flow of electricity
resistance practical in series and parallel method
- construct circuit in series with two resistors, an open switch, a cell, ammeter, voltmeter
- switch on power supply and close the switch, record voltage and current shown
- construct new circuit by rearranging the resistors from series to parallel
- switch on power supply and close the switch. record the voltage and current for this circuit
- calculate total resistance of each current using v=I X R
results of resistance in series circuits from practical
adding resistors in series increases the total resistance of the circuit
result of resistance of parallel circuits from practical
the more resistors you add, the smaller the resistance
difference in resistors
for some resistors the R value remains constant and for others it doesn’t and can change as the current does
what does the ohmic conductor graph show
current is directly proportional to potential difference
straight line through origin
describe the filament bulb graph
as current increases so does temperature so it becomes harder for current to flow
graph becomes less steep
describe diode graph
current only flows in one direction
resistance is high in the other direction so no current can flow
resistance practical in a wire method
- construct circuit you have drawn
- set length of wire to 10 cm using croc clip
- close switch and measure resistance and record
- open switch and increase length of wire to 20 cm
- record the new measurement for resistance
- continue to do this for every 10cm up to 70cm
what is the result of resistance in a wire practical
resistance is directly proportional to length
what is the current like in series circuits
same current through each component
potential difference in series circuits
total pd of power supply is shared between the components
resistance in series circuits
resistance will add up to make total resistance
current in parallel circuits
total current through the whole circuit it the sum of the currents through the separate components
potential difference in parallel
pd across each component is the same
voltage of mains electricity
230 v
frequency of mains electricity
50 Hz
what are everyday appliances designed to do
bring about energy transfers
what does amount of energy an appliance transfers depend on
how long the appliance is switched on for, and its power
what is AC
alternating current , constantly changing direction 230V and 50Hz
