Controlling and using electric current Flashcards
How is the current in a electric circuit measured
where is the ammeter placed
how is the potential difference (voltage) across a component is measured
where is the voltmeter placed in reference to the component
what is the potential difference
how does the size of the current change if the potential difference (voltage) of the power is changed
what happens to a current in a series circuit
Explain how current is conserved at a junction
the number of electrons leaving the junstion each second is the same as the total number arriving each second.
the electrons join up at the end again
what is the resistance of a component
what are the units for resistance
explain the link between resistance and current
how can the resistance of a circuit be changed
Use the equation: potential difference (volt, V) = current (ampere, A) * resistance (ohm, )
explain the effect of a filament lamp on voltage and resistance
explain the effect of a diode on voltage and resistance
explain the effect of a light-dependent resistors on voltage and resistance
explain the effect of a thermistor on voltage and resistance
Explain why, when there is an electric current in a resistor, there is an energy transfer which heats the resistor
Distinguish between the advantages and disadvantages of the heating effect of an electric current
Use the equation: electrical power (watt, W) = current (ampere, A) * potential difference (volt, V)
Use the equation: energy transferred (joule, J) = current (ampere, A) * potential difference (volt, V) * time (second, s)
