ph1bA_08_q3s

ph1bA_08_q3s - Ph1b Analytic Quiz 3 Solution Chefung Chan,...

Info iconThis preview shows pages 1–2. 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
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Ph1b Analytic Quiz 3 Solution Chefung Chan, Winter 2008 Problem 1 (6 points total) A spherically symmetric charge distribution is given by ( r ) = 0 ; < r < a = K r ; a < r < b = 0 ; r > b where K is a constant. At the center, r = 0, there is a point charge q . (a) (2 points) Use Gausss Law to find the electric field E ( r ) in the region a < r < b in terms of q, K, a, and r . Solution: Consider Gauss law with a spherical gaussian surface, we have E (4 r 2 ) = 4 q enclosed In this case, charge enclosed has 2 components. One is the center point charge q while another one is the charge distribution. For the distribution one : q ( r ) = Z r a 4 r 2 ( r ) dr = Z r a 4 Kr dr = 2 K ( r 2 a 2 ) E ( r ) = 1 r 2 q enclosed = 1 r 2 ( q + 2 K ( r 2 a 2 ) ) = q r 2 + 2 K 1 a 2 r 2 ( a < r < b ) (b) (1 point) Find the value of K in terms of q and a for which the electric field is a constant E (independent of r ) in the region a < r < b Solution: From (a), E...
View Full Document

This note was uploaded on 04/28/2010 for the course PH 1b Anal taught by Professor Mckewn during the Winter '08 term at Caltech.

Page1 / 4

ph1bA_08_q3s - Ph1b Analytic Quiz 3 Solution Chefung Chan,...

This preview shows document pages 1 - 2. Sign up to view the full document.

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