currents and symbols Flashcards
what is current
the flow of electrical charge
what will electrical charge only flow around
a complete closed circuit, if there is a potential difference, so a current can only flow if there is a source of potential difference
what is the unit of current
ampere
what is the value of a current in a single closed loop circuit
the value is the same everywhere in the circuit
what is potential difference
the driving force that pushes the charge around
what is the unit of potential difference
volt
what is resistance
anything that can slow down the flow of charge
what is the unit for resistance
ohm
what does the current flowing through a component depend on
potential difference across the current and the resistance of the component
what happens the greater the resistance acorss a component
the greater the resistance acorss a component, the smaller the current that flows
how do you work out the charge flow
charge flow = current x time
what is charge flow measured in
coulombs
what is time measured in
seconds
