Magnets and Electricity

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Magnets and Electricity

• Write-On Grade 5

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Learner Expectations

• Content Standard 14.0 Energy
• The student will investigate energy and its uses.
• Learning Expectations
• 14.1 Know that energy exists in many forms.
• 14.2 Recognize the characteristics of light
  energy and sound energy.
• 14.3 Recognize the properties and uses of
  magnets.
• 14.4 Recognize the basic concept of electricity.

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In this activity you will

• Learn about magnetism and electricity.
• Write a paragraph using three facts about
  magnetism and three facts about electricity.

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What is magnetism?

• Magnetism is the force of attraction between
  magnets and magnetic objects.

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Characteristics of magnets

• Every magnet has two poles (North and South)
• Every magnet has a magnetic field around it.
• The magnetic field is lines of force running from
  the north-seeking pole to the south-seeking pole
  of the magnet

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What do you know of that has a North and South
Pole?

• If you answered The Earth you were right!
• The Earth is one giant magnet. It has two
  magnetic poles and is surrounded by a magnetic
  field.
• This magnetic field is what causes the needle of
  a compass to point in different directions and
  causes the poles of a magnet to point either
  north or south.

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Do opposites attract?

• Yes!
• The north and south seeking poles of two magnets
  attract each other- magnetic force pulls them
  together.
• But if you try to bring two of the same poles
  (two norths or two souths) together they will
  repel each other.

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Magnets and electricity

• Magnets are used to generate, or produce,
  electricity.
• Spinning a coil of wire inside a magnetic field
  produces an electric force between the ends of
  the coil.
• In a similar way, an electric current produces a
  magnetic field around it.

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Electromagnet

• A temporary magnet made by passing electric
  current through a wire coiled around an iron bar.
• A junkyard is one place to see an electromagnet
  in action. A crane holding a huge electromagnet
  can be used to pick up scrap metal when current
  flows through it. When the crane operator wants
  to drop the scrap, he or she will simply shut off
  the current to the electromagnet.

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Ten Facts about Magnets (from the book Driving
Force)

• 1. North poles point north, south poles point
  south.
• 2. Like poles repel, unlike poles attract.
• 3. Magnetic forces attract only magnetic
  materials.
• 4. Magnetic forces act at a distance.
• 5. While magnetized, temporary magnets act like
  permanent magnets.

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• 6. A coil of wire with an electric current
  flowing through it becomes a magnet.
• 7. Putting iron inside a current-carrying coil
  increases the strength of the electromagnet.
• 8. A changing magnetic field induces an electric
  current in a conductor.
• 9. A charged particle experiences no magnetic
  force when moving parallel to a magnetic field,
  but when it is moving perpendicular to the field
  it experiences a force perpendicular to both the
  field and the direction of motion.

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• 10. A current-carrying wire in a perpendicular
  magnetic field experiences a force in a direction
  perpendicular to both the wire and the field

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Writing Activity

• Write a paragraph about magnetism and electricity
  including three facts about each that you learned
  during this presentation.