Movement of charges
Movement of charges
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Movement of charges
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Electrostatic induction
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Through electrostatic induction we have given a permanent charge to an object without touching it.
Example:
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Water is a dipole en has opposite charges on each
side
What happens when we approach with a negative charged PVC tube?
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Flow of water
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Here we have a neutral metallic sphere close to a positive charged object.
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The negative charges
move to the left. They
are more attracted
compared to the
positive charges
because the negative
charges are closer.
How can we attract neutral, non conductive paper strips with a charged object?
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In this atom the orbit of the electron is
warped toward the positive charge,
creating a dipole.
What happens in the paper?
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The atoms form dipoles
and are attracted by the
positive charge.
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Conductors and insulators
Conductor: electrons in outer layer: loosely bound, move around freely.
Nucleus
Nucleus
Nucleus
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Conductors and insulators
Insulator: No loosely bound electrons. No free moving electrons.
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Conductors and insulators: examples
Conductors
Iron
Insulators
Rubber
metals
Copper
Plastics
Ceramics
Conductive plastics: polyacethylene
Nerve cell
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