This preview shows pages 1–6. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Lecture 16 Magnetic Fields generated by Currents Good luck tonight! Sources of B field B fields exert forces on moving charges and currents (ch. 27) Oersted experiment makes it clear that currentcarrying wires exert forces on compass needles Moving charges and currents generate B fields (ch.28) B generated by a moving charged particleread 28.1 B generated by currentsour primary focus for today Demos: Oersted/tangent galvanometer BiotSavart law (circa 1820) ( of a current element) 2 2 4 sin 4 r r l Id B d r Idl dB in in = = B = B = I dl r (dB out) (dB in) = 4 x 107 Tm/A Integrate along wire path to get total contribution to B at point P P B d Field lines around current element (end/axial view) B for a finite straight wire segment ) sin (sin 4 cos 4 cos cos cos 4 2 1 2 2 2 1 2 1 2 + = = =  x I B d x I B x xd I B x Idl P 1 2 For an wire, 1 and 2 go to 90...
View Full
Document
 Spring '08
 DaveWinn
 Charge, Current, Force

Click to edit the document details