Current Electricity

An electrical current is a flow of charged particles (electrons or ions) through a circuit

In a circuit with a battery or chemical cell, electrons flow from a negative terminal to a positive terminal through the circuit

Conductors are materials through which a current can flow Metals are good conductors Other materials like carbon or water are also good conductors

Schematic diagrams are diagrams of electric circuits Symbols are used to represent different parts of an electrical circuit

Schematic Diagram

Series and Parallel Circuits Series circuits have a single pathway for the current Parallel circuits have more than one pathway for the current

Meters are used to measure current, voltage or resistance in a circuit

Current a measure of the number of charged particles passing a point in a given time measured in amperes (A) or amps 1A = 1 coulomb of charge per second Symbol for current is I

An ammeter is used to measure current in a circuit Ammeters are connected in series

Conventional Current In an electric circuit, electrons actually flow from the negative terminal to the positive terminal In conventional current, we assume they are flowing from positive to negative

Voltage a measure of the amount of electrical energy carried by each charged particle in a circuit measured in Volts (V)

A voltmeter is used to measure voltage A voltmeter is connected in parallel

Resistance A resistor resists the flow of current in a circuit Resistors convert electrical energy into other forms such as heat or light Resistance (R) is measured in Ohms (Ω) Resistance