Electrical Circuits

Electrical Circuits

1. Electric current flows in a circuit.

2. Current

   • An ammeter is used to measure current.
   • Current is measured in amps.
   • The current is the same all the way around a series circuit.

3. Circuits

   • A complete circuit is needed.
     • Parallel circuits.
     • Series circuit
     • Circuit symbols are used to draw circuit diagrams.
       • Bulb
       • Switch
       • Cells

4. Voltage

   • Voltage pushes the current around the circuit.
   • Voltage is produced by a cell. It is measured in volts.
   • Two or more cells make a battery.
   • The first cell was made by Alessandro Volta.
   • Luigi Galvani discovered that nerves carry electric current around the body.

5. Resistors

   • Resistors reduce the current.
   • Variable resistors can be used as dimmer switches.
   • These change the resistance.

6. Stop Current

   • A fuse melts to stop too high a current from flowing.
   • Circuit breakers can be used instead of fuses.
   • There are hazards when using mains electricity in the home.