Lecture 10 - Electric Field and Potential Definitions Electric field is the negative gradient of potential E = gradV ="V!V!V!V Ey = Ex = Ez =!y!x!z

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Definitions: q F E ! ! = q U V el = Electric Field and Potential Potential Difference: ! " = " = # f i l d F W U ! ! int ! " = # f i l d E V ! ! i f dl F ! " = " f i i f l d E V V ! ! In general, integration path may be complex Electric field is the negative gradient of potential: x V E x ! ! " = y V E y ! ! " = z V E z ! ! " = ! E = ! grad V = ! ! " V For very short path: l E V ! ! ! " = ! ! V = " E x ! x + E y ! y + E z ! z ( )
Background image of page 1

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

View Full DocumentRight Arrow Icon
What is E inside metal? E = 0 ! V = V f " V i = " ! E d ! l i f # What is the potential difference ( V f – V i ) ? 0 = ! V Is V zero everywhere inside a metal? No! But it is constant In static equilibrium Potential Difference in Metal In static equilibrium the electric field is zero at all locations along any path through a metal. ! V = " E x ! x + E y ! y + E z ! z ( ) The potential difference is zero between any two locations inside the metal, and the potential at any location must be the same as the potential at any other location. i f
Background image of page 2
Metal is not in static equilibrium: When it is in the process of being polarized When there is an external source of mobile charges (battery) ! V = " ! E d ! l i f # If a metal is not in static equilibrium, the potential isn’t constant in the metal. Potential in Metal Not in static equilibrium Nonzero electric field of uniform magnitude E throughout the interior of a wire of length L .
Background image of page 3

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

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/10/2010 for the course PHYS 272h taught by Professor Staff during the Spring '08 term at Purdue University-West Lafayette.

Page1 / 21

Lecture 10 - Electric Field and Potential Definitions Electric field is the negative gradient of potential E = gradV ="V!V!V!V Ey = Ex = Ez =!y!x!z

This preview shows document pages 1 - 4. Sign up to view the full document.

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