Notes

1
SPI 080712.2 Electromagnets
Notes
Science
Tennessee SPI Objective Describe the basic
principles of an electromagnet.
Instructions 1) First click on "View" from the
top-menu bar. 2) Then click on "Slide Show" from
the drop-down menu. 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?
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SPI 080712.2 Electromagnets
Notes
Science
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.

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SPI 080712.2 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
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SPI 080712.2 Electromagnets
Notes
Science
Electromagnets Three Main Components

• (1) Solenoid , (2) Iron Core, (3) Source of
  electricity

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SPI 080712.2 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)

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SPI 080712.2 Electromagnets
Notes
Science
How do we use electromagnets?

• To lift objects Example Junkyard crane-magnets
• Video Clip Scrapyard Electromagnet In Action

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SPI 080712.2 Electromagnets
Notes
Science
How do we use electromagnets?

• To lift objects Example Maglev trains (magnetic
  levitation)
• Video Clip (show 1st 45 sec) How Maglev Trains
  Work

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SPI 080712.2 Electromagnets
Notes
Science
How do we use electromagnets?

• To propel objects Example Railguns as weapons
• Video Clip (stop at 2 min15 secs) US Navy
  Railgun

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SPI 080712.2 Electromagnets
Notes
Science
How do we use electromagnets?

• To propel objects Railguns as launch platforms
  (for spacecraft)

• NASA is testing spacecraft launch railguns to
  replace rockets

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SPI 080712.2 Electromagnets
Notes
Science
How do we use electromagnets?

• To propel objects Railguns as launch platforms
  (for aircraft)
• Video Clip (stop at 108 secs) Electromagnetic
  Catapult

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SPI 080712.2 Electromagnets
Notes
Science
How do we use electromagnets?

• To Look Inside of People Magnetic Resonance
  Imaging (MRI)
• Video Clip MRI Magnetic Field Strength

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SPI 080712.2 Electromagnets
Science
Questions
Here is an example of a question you might see on
a quiz or test.
13
SPI 080712.2 Electromagnets
Science
Questions
Here is an example of a question you might see on
a quiz or test.
14
SPI 080712.2 Electromagnets
Science
Questions
Here is an example of a question you might see on
a quiz or test.
15
SPI 080712.2 Electromagnets
Science
Questions
Here is an example of a question you might see on
a quiz or test.
16
SPI 080712.2 Electromagnets
Science
Questions
Here is an example of a question you might see on
a quiz or test.