Physics 121: Electricity

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Physics 121 Electricity Magnetism Lecture 1

• Carsten Denker
• NJIT Physics Department
• Center for SolarTerrestrial Research

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Electric Charge

• Electromagnetism
• Electric Charge
• Conductors and Insulators
• Coulombs Law
• Charge is Quantized
• Charge is Conserved

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Coulombs Law
Coulombs law
Gravitational force
Coulombs law
Charge transfer
Superposition principle
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Theorems and Definitions
Charges with the same electrical sign repel each
other, and charges with opposite electrical sign
attract each other. One Coulomb is the amount of
charge that is transferred through the cross
section of a wire in 1 second when there is a
current of 1 Ampere in the wire. A shell of
uniform charge attracts or repels a charged
particle that is outside the shell as if all the
shells charge were concentrated at its
center. If a charged particle is located inside a
shell of uniform charge, there is no net
electrostatic force on the particle from the
shell.
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Charge is Quantized and Conserved
Radioactive decay
Annihilation
Pair production