Electrons, Photons

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Electrons, Photons Waves
Module 1 Electric Current

• Explain that electric current is a net flow of
  charged particles.
• Explain that electric current in a metal is due
  to the movement of electrons, whereas in an
  electrolyte the current is due to the movement of
  ions.
• Explain what is meant by conventional current and
  electron flow.
• Select and use the equation ?Q I?t.
• Define the coulomb.

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Electrons, Photons Waves
Module 1 Electric Current
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Electrons, Photons Waves
Module 1 Electric Current
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Electrons, Photons Waves
Module 1 Electric Current
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Electrons, Photons Waves
Module 1 Electric Current
Q I x t
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Electrons, Photons Waves
Module 1 Electric Current
The Coulomb One coulomb is the total charge
supplied by a current of one ampere in a time of
one second.
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Electrons, Photons Waves
Module 1 Electric Current

• Recall and use the elementary charge e 1.6
  10-19 C.
• Describe Kirchhoffs first law and appreciate
  that this is a consequence of conservation of
  charge.
• State what is meant by the term mean drift
  velocity of charge carriers.
• Select and use the equation I Anev.
• Describe the difference between conductors,
  semiconductors and insulators in terms of the
  number density n.

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Series Circuits
Electrons, Photons Waves
Same Value Resistors
A3
A1
A2
V1
V2
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Series Circuits
Different Value Resistors
A3
A1
A2
V1
V2
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Parallel Circuits
Same Value Resistors
A3
A1
V1
A2
V2
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Parallel Circuits
Different Value Resistors
A3
A1
V1
A2
V2
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Drift Velocity

• state what is meant by the term mean drift
• velocity of charge carriers
• select and use the equation I Anev
• describe the difference between conductors,
• semiconductors and insulators in terms of the
• number density n.

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Drift Velocity
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Drift Velocity
The mean drift velocity is the average
displacement travelled by the electrons along
the wire per second
I Anev
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Drift Velocity
I Anev