Current Electricity Flashcards
An electric current is caused by
The flow of electrons through a good conductor such as a metal
A closed circuit is need for the current
To flow, if there is a break in a circuit the current won’t flow. The electrical energy can’t get through
Energy provided
By a battery or paper pack, it is needed to move the current around the circuit
The battery pumps electrons
From its negative end around a circuit
The electrons are attracted
Back to the positive side no of the battery
Potential difference
The difference in electrical pressure between the positive and negative end of the battery / power pack
Wh never there is q potential difference
Electricity will flow
This potential difference is known as
Voltage and is measured in volts
Resistance
Is the opposition to the flow of electrons. The unit is Ohm and it is measured using an ohmmeter
If a resistor is placed in a electric circuit
It will slow down the flow of electrons
Current
Symbol = I
Unit = Ampere
Unit Symbol = A
Measured using = Ammeter
Potential Difference / Voltage
Symbol = V
Unit = Voltage
Unit Symbol = V
Measured using = Voltmeter
Resistance
Symbol = R
Unit = Ohm
Unit Symbol = Omega
Measured using = Ohmmeter
Bulbs in series
If a bulb in series blows , none of them turn on.
The same amount of current flows through each bulb in the series.
The voltage is split up, depending on the size of the bulb.
Bulbs in Parallel
The lights in your house are connected in parallel , as are car head lights.
If bedroom light blows , the kitchen light is unaffected.
The current is split between the bulbs , if they are the same size, then the current is split evenly.
The same voltage flows through each bulb, so they are brighter than those series
