Circuits and Resistors- Higher OCR
1) Current is the flow of charge (electrons) around a circuit.
Current will only flow through a component if there is a voltage across that component.
Current is measures in amps, A.
2) Voltage is the driving force that pushes the current round. Voltage is measured in volts, V.
3) Resistance is anything in the circuit that reduces the current. Resistance is measured in ohms, O.
4) There's a balance- the relative sizes of voltage and resistance decide how big the current will be. If you increase the voltage, then more current will flow. If you increase the resistance, then less current will flow. (or more voltage will be needed to keep the current flowing)
Learn the CIRCUIT SYMBOLS FOR:
(like below without the arrow)