Lec02-2 - cture 2-1 COULOMB FORCE 1 2 2 ˆ q q F k r r = r...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: cture 2-1 COULOMB FORCE 1 2 2 ˆ q q F k r r = r Charge q 1 “Test Charge” q 2 r 1,2 1,2 1,2 Question : How can q 1 sense q 2 without direct contact? • NO! just as air around us, there’re some medium around a charge, the electric field that transfers the force. “Is action at a distance possible?” cture 2-2 READING QUIZ 1 HOW DOES THE MAGNITUDE OF THE ELECTRIC FIELD E FROM A POINT CHARGE Q DEPEND ON THE MAGNITUDE OF Q AND THE DISTANCE R TO THE FIELD POINT? A) E = k Q Q / R 2 A) E = k Q / R B) E = k Q / R 2 C) E = k Q Q / R A) E = k Q / R 3 cture 2-3 Electric Field Define electric field , which is independent of the test charge, q 2 , and depends only on position in space: F E q = ur ur 2 1 ˆ 4 F Q E r q r πε = = r r Electric Field due to a Point Charge Q cture 2-4 Electric Field Lines • A visualization tool to illustrate the geometry of an electric field. • Electric field lines originate from positive charges and terminates at negative charges . • The direction of the electric field at any location is tangential to the field line there. • The magnitude of the electric field at any location is proportional to the density of the lines there. # lines/area ~ 1/r 2 ~ |E| (or at infinity) cture 2-5 Electric Field With this concept, we can “map” the electric field anywhere in space A Vector field 77 82 83 68 55 66 83 75 80 90 91 75 71 80 72 84 73 57 88 92 77 56 88 73 64 cture 2-6 Demonstration Vandegraaff Generator and Insulators and Conductors cture 2-7 Electric field lines of two charges of equal magnitude dipole Far from the charges, electric...
View Full Document

This note was uploaded on 12/07/2011 for the course PHYS 241 taught by Professor Wei during the Fall '08 term at Purdue.

Page1 / 25

Lec02-2 - cture 2-1 COULOMB FORCE 1 2 2 ˆ q q F k r r = r...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online