Transcript Powerpoint Slides - University of Calgary

THE USE OF HISTORY TO
IMPROVE SCIENCE EDUCATION
Differentiation between
magneto-statics and electrostatics
By Varda Bar
And Igal Galili
Hebrew University of Jerusalem
Parallelism between children’s
and historical ideas
 There
are many instances of this
Parallelism.
 Gravity,
magnetism, and force are only
three examples.
Debates about scientific issues of
the past can help educators
 Understand
why children might be
confused about certain concepts.
 Get ideas for how to clarify ideas and
resolve conflicts.
 Pick up suggestions for activities.
 Use historical anecdotes to provoke
conceptual change.
Electrostatics and magneto-statics
 Pupils
confuse electric current with
magnetism
 Pupils
confuse electrostatic phenomena
with magneto-static phenomena.
Example: “Magnetic Current”
Adults and children have said:
 “Electrical current causes magnetic charges.”
 “The current makes lights caused by magnetism.”
 “The magnet pushes the current, it is the
electrical current that works together with
magnetism”
 “Electrical current causes magnetic motion.”
 “Electricity moves in the wires causing friction,
which bring out magnetic attraction.”
Example: Magnetic Attraction
“Electrical attraction was caused by
magnetism.”
 “The paper was attracted to the comb by its
magnetism.”
 “During thunder and lightning the clouds are
attracted to each other by their magnetism.”
 “Any attraction is due to magnetic force.”
 “Electric current is also caused by magnetism.”

William Gilbert 1600
 Wrote
the first
significant scientific
book about
magnetism, called
“De Magnete.”
William Gilbert 1600
 Was
the first person to differentiate
between magnetic force and the
electrostatic force produced by amber.
 Suggested the rotating Earth with its
magnetic field.
William Gilbert 1600
 Johannes
Kepler and Galileo were very
interested in Gilbert's magnetic
researches because the Copernican
cosmology needed a new physics to
support it.
 Galileo praised Gilbert. Galileo’s efforts
to make a truly powerful lodestone for his
patrons probably date from his reading of
Gilbert's book.
Confusion in Gilbert’s Time (1600)
 In
Gilbert’s period electrostatics and
magnetism were not separated.
 Both forces acted at a distance.
 Both forces attracted as well as repelled.
Magnetism
Electricity

Only iron and load stone

Many materials

Permanent

Temporal

Not activated by rubbing

Activated by rubbing

Not affected by water

Diminished in the
presence of humidity
Successful Learning
Opportunities
 Simple
experiences for elementary
school pupils.
 Were used to help them differentiate
electrostatic from magneto-static
attractions.
 These experiences helped the teacher
relate the cause of natural phenomena
to electrostatic attractions