1. Science
Notes: Stnd 01
Date
Standard 01: 8.PS2.1
Magnetism and Electricity
Design and conduct investigations depicting the relationship between magnetism and electricity in electromagnets, generators, and electrical motors, emphasizing the factors that increase or diminish the electric current and the magnetic field strength.
Science and Engineering Practice(s)
Develop and Use Models, Obtain and communicate information, Construct Explanations
Crosscutting Concepts
Cause and Effect, Systems and Systems Models
I Can Statement
...I can explain and demonstrate cause and effect relationships
between magnetism and electricity.

2. Magnetism and Electricity
Notes
Stnd 01:
Magnetism and Electricity
Science
Magnetic Fields
An invisible magnetic field exists around all magnets. N S

3. You can see the magnetic field lines by using fine iron filings.
Magnetic Fields
You can see the magnetic field lines by using fine iron filings.
Note: field lines are concentrated at the ends (called poles)
Note: polarity is the property of having two opposing roles.
North Pole
South Pole

4. Magnetism and Electricity
Notes
Stnd 01:
Magnetism and Electricity
Science
North and South Poles
All magnets have these poles regardless of their shape.
If you cut a magnet in half, each half will still have these two poles (north and south)
Bar magnet
Horseshoe Magnet
Donut magnet

5. F.Y.I: Why Are Some Substances Magnetic?
All atoms have magnetic fields with north and south poles.
Atoms in objects are found in areas called domains.
If the poles line up facing the same direction, this makes the object magnetic.
If they don’t line up, it is not magnetic.

6. Magnetism and Electricity
Notes
Stnd 01:
Magnetism and Electricity
Science
Magnetic Forces
magnets exert force on other magnets
“Opposites attract”
(North & South pull towards each other) N S
“Like repels”
(North & North or South & South push away) N S

7. Electromagnets
Electric current in the wire produces a magnetic field which lines up atoms in the domains of the iron core forming an electromagnet.
Simple Electromagnet
Iron Core
Source of
Electricity
Solenoid
An electromagnet consists of a solenoid wrapped around an iron core attached to a source of electricity

8. Electromagnetic Induction
Magnets and a coil of wire can induce (generate) electricity
This process is called electromagnetic induction
Note: another name for electricity is electrical current
Note: another name for a coil of wire is a solenoid
Simple Electrical Generator
Coil of Wire
(Solenoid)
Bar Magnet

9. Electromagnetic Induction
The magnet has to move through the coil
… or the coil has to move through the magnet
Simple Electrical Generator
Here is the magnet
Galvanometer
Here is the solenoid
(coil of wire)
Here is a Galvanometer
(measures electric current and direction of the current)
Solenoid
The bar magnet is pushed back and forth
through the solenoid
Magnet

10. How It Works All magnets have an invisible magnetic force field.
The bar magnet is pushed back and forth
through the solenoid
Simple Electrical Generator
The magnetic force field pushes the electrons from atom to atom in the wire creating electrical current.

11. Look at the two generators shown below
Generators convert mechanical energy into electrical energy
Both diagrams are showing electromagnetic induction.
Note: in picture 01 the wire coil is stationary and the magnet is moving back and forth
Note: in picture 02 the magnet is stationary and the wire coil
is rotating
Picture 02
(It works either way)
Picture 01

12. Rotational Generators
(very common)
Note: the magnet is stationary and the wire coil is rotating.
It also works if the wire is stationary and the magnet is moving
Rotational Generator
Magnet
Magnet
Wire Coil

13. F.Y.I.-Electromagnetic Induction
…is how most electricity is generated around the world.
These power plants all use magnets and coils of wire to make electricity
Nuclear Power Plant
Wind Turbines
Coal Power Plant
Hydroelectric Dam

14. F.Y.I.-Electromagnetic Induction
…is how most electricity is generated in cars, trains, boats, & planes
Each of these machines has a generator inside that creates electricity
Electrical Generator
(Alternator)
Consists of a magnet rotating through a
coil of wire

15. Two Ways to Increase the Electrical Current
(1) Move the magnet faster
(2) Add more coils of wire

16. Brainpop Video Notes Science
Stnd 01:
Magnetism and Electricity
Science
Brainpop Video
View the video titled "Electromagnetic Induction”
Link: Brainpop Website
Duration: 2 min 25 sec
User name: (ask your teacher for the user name)
Password: (ask your teacher for the password)
Task 01: Write down five things that catch your attention as
you watch this video.
Task 02: Complete the Brainpop quiz.