hw5 - Physics 21 Fall, 2009 Solution to HW-5 Potential near...

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: Physics 21 Fall, 2009 Solution to HW-5 Potential near a Charged Sheet Let A = ( x 1 , y 1 ) and B = x 2 , y 2 ) be two points near and on the same side of a charged sheet with surface charge density + . The electric field E due to such a charged sheet has magnitude E = 2 everywhere, and the field points away from the sheet, as shown in the diagram. (a) What is the potential difference V AB = V A V B between points A and B ? (b) If the potential at y = is taken to be zero, what is the value of the potential at a point V A at some positive distance y 1 from the surface of the sheet? (c) Now take the potential to be zero at y = 0 instead of at infinity. What is the value of V A at point A some positive distance y 1 from the sheet? (a) Points A and B are on the same side of the sheet, so V A V B = Z A B E d l = E ( y 2 y 1 ) The potential difference is positive ( V A V B > 0) because the line integral is evaluated in the direction opposite to the electric field lines. One can also say that it takes positive work to move a positive charge from B to A because one must push against the field. (b) If we move point B to y 2 = , where V B = 0, then the formula above gives V A = . (c) If we move point B to y 2 = 0, where V B = 0, then the formula above gives V A = y 1...
View Full Document

Page1 / 2

hw5 - Physics 21 Fall, 2009 Solution to HW-5 Potential near...

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