4th Grade Physical Science: Electricity and Magnetism

1
4th Grade Physical Science Electricity and
Magnetism

• Electricity
• How to design and build a series and parallel
  circuit
• A series circuit only has one path for moving
  charges when the path is broken, the energy
  cant flow.
• A parallel circuit has two or more paths for
  moving charges.

2
4th Grade Physical Science Electricity and
Magnetism

• Electricity
• Electrical energy can be converted to heat,
  light, and motion
• The heat given off when something is plugged in
• Flashlights
• Fans

3
4th Grade Physical Science Electricity and
Magnetism

• Electricity
• Electrically charged objects attract or repel
  each other
• 2 balloons rubbed with a piece of wool will have
  the same (like) electrical charge.
• The balloons will move away from each other
  because like charges repel each other

4
4th Grade Physical Science Electricity and
Magnetism

• Magnetism
• The space near a magnet where magnetic forces act
  is called the magnetic field
• Magnets have opposite poles at each end, and
  unlike poles attract like poles repel

5
4th Grade Physical Science Electricity and
Magnetism

• Magnetism
• How to create a simple compass and how to use it.
  
• A needle or some other wire-like piece of steel
  (a straight paper clip, for example)
• Something small that floats (a piece of cork, the
  bottom of a Styrofoam coffee cup, a piece of
  plastic or a milk jug cap)
• A dish, like a pie plate, 9 to 12 in diameter,
  with about an inch of water in it

• The first step is to turn the needle into a
  magnet. The easiest
• way to do this is with another magnet -- stroke
  the magnet along
• the needle 10 or 20 times.

6
4th Grade Physical Science Electricity and
Magnetism

• Magnetism

Place your float in the middle of your dish of
water as shown below. The "float on water"
technique is an easy way to create a nearly
frictionless bearing. Center your magnetic needle
on the float. It very slowly will point toward
north. You have created a compass!
7
4th Grade Physical Science Electricity and
Magnetism

• Magnetism
• Electromagnetism
• Wires carrying an electric current become
  magnets.
• An electromagnet is a core wrapped with wires
  that carry current.
• The ends of the electromagnet are magnetic only
  when there is current in the wire.
• Generators use electromagnets to produce current
  (electricity) from motion.
• Motors use electromagnets to convert electricity
  to motion.