Download Week 7: Magnetic Fields and Magnetic Fields due to Currents

Applied Physics II : SCS139
Week 7
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Weekly Outline
• Magnetic Fields
• Magnetic Fields due to Currents
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Magnetic Fields
Definition of the magnetic field:
B
q
v
When a charged particle moves
inside a magnetic field, there is
a force due to the field on the
particle. This amount of force is
used to defined the magnetic field.
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Magnetic Fields
F is always perpendicular to v. No change in
kinetic energy.
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Magnetic Fields
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Magnetic Field Lines
North pole
South pole
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Magnetic Field Lines
North pole
South pole
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Crossed Fields: Thompson’s Experiment
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A Circulating Charged Particle
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A Circulating Charged Particle
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A Circulating Charged Particle
nonuniform magnetic field
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A Circulating Charged Particle
nonuniform magnetic field
The Aurora
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The Cyclotrons
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Magnetic Force on a Current-Carrying Wire
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Torque on a Current Loop
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Torque on a Current Loop
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Magnetic Fields Due to Currents
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Magnetic Fields Due to Currents
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Magnetic Fields Due to Currents
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Magnetic Fields Due to Circular Arc of Wire
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Force Between Two Parallel Currents
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Ampere’s Law
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Ampere’s Law
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Ampere’s Law
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Solenoids
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Solenoids
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Toroids
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Magnetic Dipole Moment
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A Current-Carrying Coil as a Magnetic Dipole
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A Current-Carrying Coil as a Magnetic Dipole
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