This document provides an overview of electricity including: - Defining electricity and discussing how it is created and its benefits to society. - Explaining that electricity is the flow of electrons called electric current, and outlining conventional current flow. - Distinguishing between conductors that allow current to flow and insulators that prevent it. - Stating that a power source is needed to push electrons through a circuit and outlining different power sources. - Introducing Ohm's Law which relates voltage, current, and resistance and provides an example calculation. - Noting that a multimeter can be used to measure voltage, current, and resistance. - Assigning students an activity to measure resist

1. ELECTRICITY
Day1

2. Goals for the Lesson
• Discuss how electricity is created and benefits it bring to
society.
• Understand the principles of electricity and the terms used
when discussing electricity
• Be able to state Ohms Law and its formulas.
• Use a multimeter to measure voltage and resistance.

3. What is Elecricity
• Definitions
• noun
• any phenomenon associated with
stationary or moving electrons, ions, or
other charged particles
• the science concerned with electricity
• an electric current or charge ⇒ a motor
powered by electricity
• emotional tension or excitement, esp
between or among people
• http://www.collinsdictionary.com

4. Current Flow
Electricity is the flow of
electrons and this flow of
electrons is called electric
current.
The current flows from
negative to positive but
due to a lack of
understanding about
electricity when it first was
discovered it was thought
it flowed from positive to
negative this idea was
kept and we call it the
conventional current flow

5. Conductors & Insulators
• Conductors allow current • Insulators prevent current
to flow through them flowing through them
easily example copper, plastics, wood and rubber
aluminium, gold metals are example of good
are good conductors insulators

6. Power source
A power source is required to
push the electron around a circuit.
The force that pushes the
electrons are called volts symbol
(V ). The power source can be
mains supplied which is
Alternating current AC or
battery powered Direct Current
DC. Alternating current changes
from positive to negative in
waves called cycles, the ESB
supplies alternating current at 220
volts and 50 cycles a second.
Direct current flow in the same
direction all the times, this is the
type of current is stored in a
battery

7. Ohms Law
When we talk about electricity These three values are
it has a relationship between expressed in ohms law which
three values voltage, current states that:
and resistance. The current flowing through a
Voltage is the force electrons conductor is proportional to the
are pushed around a circuit potential difference across it
symbol (V ) units volts provided the temperature stays
Current is the rate or speed the same. This can be
the electrons move symbol (I) expressed as a formula
units ampere (A).
Resistance this is the ability of
some conductors to resist the
flow of electrons, this allows
us to control the flow symbol
R units ohms Ω

8. Ohms Law Example
Question
What is the resistance of a resistor that has a voltage drop
of 9.35V and a current of 0.55mA

9. Multimeter
A multi meter is a
device which can
measure voltage,
current, resistance and
check for breaks in
circuits.

10. Activity
In pairs find the resistance for the resistors given?
Home work
Study work sheet you completed in class.
Complete activity on blog in relation to ohms law.
Find and post back on blog most interesting fact you can
find on electricity.