1. Electricity
The Quick Version

2. Voltage is how much electricity, or push, measured in Volts (V)

3. Power is how much electrical energy being delivered in a unit of time, measured in Watts (W)

4. Current is the measure of electrical flow and is measured in amperes or “amps” (A) and its symbol is I.

5. Resistance slows electricity down as it moves through a circuit
Resistance slows electricity down as it moves through a circuit. It has a symbol of R and is measured in Ohms (Ω).

6. Electricity flows from areas of high volts to areas of low volts
Electricity flows from areas of high volts to areas of low volts. This is known as potential difference or voltage!

7. Equations
____ V R= I
V=I R V
____
I = R

8. Equations
P=VI

9. Electricity and Circuits
Property
Units of Measure
Voltage (V)
Current (I )
Resistance (R)
Power (P)
Volts (V)
Amps (A)
Ohms (Ω)
Watts (W)

10. Electric Circuits
An electric circuit is a network of electrical components (resistors, transmission lines, electrical sources, switches, etc.) that forms a closed loop and provides a path for electrical energy.
Circuits have three basic parts:
An energy source that converts non-electrical energy into electrical energy; examples are batteries and generators.
An output device that uses electrical energy to do work; examples are motors, lamps, and displays.
Materials to make a connection to allow electrical energy to flow; examples are wires and cables

11. Examples of Symbols for Circuit Diagrams
Component
Symbol
Function of Component
Wire
To pass current from one part of a circuit to another
Wires joined
A ‘dot’ should be drawn to show where two wires join together.
Battery
Supplies electrical energy; the larger terminal is positive (+)
Light Bulb and Socket
Converts electrical energy to light energy
Resistor
Restricts the flow of current
On-Off Switch
Allows current to flow only when it is in the ‘on’ (closed) position + -

12. Light Bulb
Resistor

13. Series Circuits
Electrical components connected in series are connected along a single path so the current only has one path to follow.
If one component in a series circuit is disconnected or fails, the entire circuit is turned off.
switch
battery
Bulb A
In the circuit to the left, what would happen if Bulb B burned out?
Bulb B
If Bulb B burned out there would be no way for the electrical energy to flow. Bulb A would not light.

14. Parallel Circuits
Electrical components connected in parallel are connected so that the current has multiple paths that it can take.
If one component in a parallel circuit is removed or fails, the other components will still have an intact path for current and will continue to work.
battery
Bulb A
Bulb B
Bulb C

15. Review Activity – Circuits Answer the questions on the Review Sheet
Review Activity – Circuits Answer the questions on the Review Sheet. After you have finished, your teacher will help you check your answers using this animation.
Switch A
Switch B
Switch C
Switch D
Bulb A
Bulb B
Bulb C
Bulb D
Batteries

16. Resistors
A resistor is a component that restricts the flow of current.
Resistance is measured in ohms. The symbol for the ohm is  (omega).
On a circuit diagram, resistors are represented by 2 4

17. THE END!!