Download Circuits and Current Electricity

CIRCUITS AND CURRENT
Recall Static Electricity
The build up of stationary electric charges
(positive and negative) on two different
surfaces.
Caused by the TRANSFER of electrons from
one place to another.
Current Electricity
The continuous flow of electrons in a
closed circuit.
What is an Electric Circuit?
A circuit is a pathway for electricity to
flow made up of four basic
components.
Component #1: The Source
Function:
Provides the circuit with electrical energy
and a supply of current (electrons).
Schematic Diagram
one-celled battery
three-celled battery
AC power supply
AC
Component #2: Conductors
Function – Wires/Wires Joined:
 Provides a path for current to flow. In
a perfect conductor no energy is lost.
The current flows with no resistance.
Function – Ground Connection:
 The ground allows electrons to flow to
the ground or from the ground.
Schematic Diagram
wire
wires joined
ground connection
Component #3: Switch
Function – Open Switch:
An open switch prevents current from
flowing in a circuit.
Function – Closed Switch:
A closed switch allows current to flow.
Function – Fuse/Circuit Breaker:
A fuse prevents a circuit from
overloading with too much current by
opening the circuit before it over heats.
Schematic Diagram
open switch
closed switch
fuse/circuit
breaker
A fuse is basically a current limiting electrical
device, designed to destroy itself instead of
the equipment they are connected to.
A circuit breaker is an electrical switch designed
to protect an electrical circuit from damage
caused by current overload or short circuit.
Its basic function is to interrupt the current flow.
Component #4: The Load
 Any
device that needs electrical
energy to function.
 The
load is designed to take the
electrical energy and converts it into
the needed form of energy.
e.g. stove, fridge, toaster, light bulb
Light Bulb
 Converts
electrical energy into light
energy.
Schematic Diagram
Resistor
A
device added to a circuit to
decrease the amount of current
(electrons) flowing in the circuit per
second.
Schematic Diagram
A Motor
 Converts
electrical energy in to
mechanical or kinetic energy
(movement).
Schematic Diagram
M
Types of Energy
 Light
Energy (e.g. light bulb)
 Heat
Energy (e.g.stove, curling iron, toaster)
 Mechanical
 Sound
or Kinetic Energy - Movement
(e.g. blender, ceiling fan)
Energy ( e.g. i-pod, radio)