1. Tennessee SPI Objective: Check for Understanding Essential Question(s)
Electromagnets
Notes
Science
Tennessee SPI Objective:
Describe the basic principles of an electromagnet.
Instructions
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3) Then use the right-arrow button on your keyboard to advance through this presentation.
Check for Understanding
Experiment with an electromagnet to determine
how to vary its strength.
Essential Question(s)
What are the basic properties of electromagnets?
How do I vary the strength of an electromagnet?

2. Notes Science SPI 0807:12.2 Electromagnets Electromagnets
An electromagnet consists of a solenoid wrapped around an iron core attached to a source of electricity
F.Y.I. -Electric current in the wire produces a magnetic field which lines up atoms in the domains of the iron core forming an electromagnet.

3. Electromagnet Properties
SPI 0807:12.2
Electromagnets
Notes
Science
Electromagnet Properties
Unlike permanent magnets, electromagnets can be turned on and off as needed.
You can adjust the strength of an electromagnet two ways
1) Use more electrical current
2) Use more coils in the solenoid

4. Electromagnets: Three Main Components
SPI 0807:12.2
Electromagnets
Notes
Science
Electromagnets: Three Main Components
(1) Solenoid , (2) Iron Core, (3) Source of electricity

5. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
Science
How do we use electromagnets?
Commonly found in electrical motors and switches
Also used to…
To lift objects
Example: Junkyard crane-magnets
Example: Maglev trains
To propel objects
Example: Railguns as weapons
Example: Railguns as launch platforms
To look inside of people
Example: Magnetic Resonance Imaging (MRI)

6. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
How do we use electromagnets?
Science
To lift objects: Example: Junkyard crane-magnets
Video Clip: Scrapyard Electromagnet In Action

7. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
How do we use electromagnets?
Science
To lift objects: Example: Maglev trains (magnetic levitation)
Video Clip (show 1st 45 sec): How Maglev Trains Work

8. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
How do we use electromagnets?
Science
To propel objects: Example: Railguns as weapons
Video Clip (stop at 2 min:15 secs): US Navy Railgun

9. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
How do we use electromagnets?
Science
To propel objects: Railguns as launch platforms (for spacecraft)
NASA is testing spacecraft launch railguns to replace rockets

10. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
How do we use electromagnets?
Science
To propel objects: Railguns as launch platforms (for aircraft)
Video Clip (stop at 1:08 secs): Electromagnetic Catapult

11. How do we use electromagnets?
SPI 0807:12.2
Electromagnets
Notes
Science
How do we use electromagnets?
To Look Inside of People: Magnetic Resonance Imaging (MRI)
Video Clip: MRI Magnetic Field Strength

12. Science Questions SPI 0807:12.2 Electromagnets
Here is an example of a question you might see on a quiz or test.

13. Science Questions SPI 0807:12.2 Electromagnets
Here is an example of a question you might see on a quiz or test.

14. Science Questions SPI 0807:12.2 Electromagnets
Here is an example of a question you might see on a quiz or test.

15. Science Questions SPI 0807:12.2 Electromagnets
Here is an example of a question you might see on a quiz or test.

16. Science Questions SPI 0807:12.2 Electromagnets
Here is an example of a question you might see on a quiz or test.