This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: Physics 21 Fall, 2011 Solution to HW15 2832 A solid conductor with radius a is supported by in sulating disks on the axis of a conducting tube with inner radius b and outer radius c . The central conductor and tube carry equal currents I in opposite directions. The currents are distributed uniformly over the cross sections of each con ductor. (a) Derive an expression for the magnitude of the magnetic field at points outside the central, solid conductor, but inside the tube ( a < r < b ). (b) Derive an expression for the magnitude of the magnetic field at points outside the tube ( r > c ). (a) This problem is best answered with Ampere’s Law contintegraldisplay B · d l = μ I encl Chose a circular line integral path with radius r between the center and outer conductor, then by symmetry we expect the value of B to be constant around the path. The only current enclosed is the current I in the center conductor. 2 πrB inside = μ I Solving for B, B inside = μ I 2 πr = ( 2 × 10 7 ) I r (b) Taking a similar approach for this problem, choose a current loop with radius...
View
Full
Document
This note was uploaded on 12/18/2011 for the course PHYS 021 taught by Professor Hickman during the Spring '08 term at Lehigh University .
 Spring '08
 Hickman
 Current, Work

Click to edit the document details