Lecture_11

# Lecture_11 - Potential at a Certain Location 1 Add up the...

This preview shows pages 1–7. Sign up to view the full content.

1. Add up the contribution of all point charges at this point V A = 1 4 πε 0 q i r i i q 1 r 1 q 2 r 2 A 2. Travel along a path from point very far away to the location of interest and add up at each step: E d l V A = E d l A q 1 q 2 A E dl Potential at a Certain Location

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

View Full Document
1. Subtract the potential at the initial location A from the potential at final location B Δ V = V B V A 2. Travel along a path from A to B adding up at each step: l d E Δ V = E d l A B A B A B E dl Finding Potential Difference
A Example: E = 0 inside a charged metal sphere, but V is not! Common Pitfall Assume that the potential V at a location is defined by the electric field at this location. E

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

View Full Document
Electric field in capacitor filled with insulator: E net = E plates -E dipoles E net = E plates K E plates = Q / A ( ) ε 0 E net = Q / A ( ) K ε 0 K – dielectric constant Dielectric Constant
= Δ B A l d E V s K E Es V plates = = Δ s E plates = Q / A ( ) ε 0 Δ V = Es = Q / A ( ) K ε 0 s K V V vacuum insulator Δ = Δ Potential Difference in a Capacitor with Insulator

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

View Full Document
Energy can be stored in electric fields E one _ plate = Q / A ( ) 2 ε 0 (for small s ) U el = Δ 2 0 2 1 ε E volume Δ U el Δ volume ( ) = 1 2 ε 0 E 2 Field energy density: (J/m 3 ) Energy expended by us was converted into energy stored in the electric field
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern