TFE4120 Electromagnetism: crash course Intensive course: 7-day lecture including exercises. Teacher: Anyuan Chen, Post-doctor in electrical power engineering, room E-421. e-post:
[email protected] Assistant: Hallvar Haugdal E-451.
[email protected]. Exercises help: proposal time 13:00-15:00 place: E-451. Paticipants: should have Bsc in electronic, electrical/ power engineering. Aim of the course: Give students a minimum of pre-requisities to follow a 2-year master program in electronics or electrical /power engineering. Webpage: https://www.ntnu.no/wiki/display/tfe4120/Crash+course+in+Electromagnetics+2017 All information is posted there . Lecture1: electro-magnetism and vector calulus 1) What does electro-magnetism mean? 2) Brief induction about Maxwell equations 3) Electric force: Coulomb’s law 4) Vector calulus (pure mathmatics) Electro-magnetism Electro-magnetism: interaction between electricity and magnetism. Michael Faraday (1791-1867) • In 1831 Faraday observed that a moving magnet could induce a current in a circuit. • He also observed that a changing current could, through its magnetic effects, induce a current to flow in another circuit. James Clerk Maxwell: (1839-1879) • he established the foundations of electricity and magnetism as electromagnetism. Electromagnetism: Maxwell equations • A static distribution of charges produces an electric field • Charges in motion (an electrical current) produce a magnetic field • A changing magnetic field produces an electric field, and a changing electric field produces a magnetic field. Electric and Magnetic fields can produce forces on charges Gauss’ law Faraday’s law Ampere’s law Electricity and magnetism had been unified into electromagnetism! Coulomb’s law: force between electrostatic charges 풒ퟏ풒ퟐ 풒ퟏ풒ퟐ Scalar: 푭 = 풌 ퟐ = ퟐ 풓ퟏퟐ ퟒ흅휺ퟎ풓ퟏퟐ 풒ퟏ풒ퟐ Vector: 푭 = ퟐ 풓ෞퟏퟐ ퟒ흅휺ퟎ풓ퟏퟐ 풓ෞퟏퟐ is just for direction, its absolut value is 1.