Physics 121: Electricity & Magnetism – Lecture 1 Carsten Denker NJIT Physics Department Center for Solar–Terrestrial Research

January 17, 2007Center for Solar-Terrestrial Research Electric Charge  Electromagnetism  Electric Charge  Conductors and Insulators  Coulomb’s Law  Charge is Quantized  Charge is Conserved

January 17, 2007Center for Solar-Terrestrial Research Coulomb’s Law Charge transfer Superposition principle Coulomb’s law Gravitational force Coulomb’s law

January 17, 2007Center for Solar-Terrestrial Research 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 shell’s 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.

January 17, 2007Center for Solar-Terrestrial Research Charge is Quantized and Conserved Radioactive decay Annihilation Pair production