## Lecture 2: Electric Field, Field Lines, Superposition, Inductive Charging, Dipoles, Induced Dipoles

author: Walter H. G. Lewin, Center for Future Civic Media, Massachusetts Institute of Technology, MIT
recorded by: Massachusetts Institute of Technology, MIT
published: Oct. 10, 2008,   recorded: February 2002,   views: 56733
released under terms of: Creative Commons Attribution Non-Commercial Share Alike (CC-BY-NC-SA)
Categories

# Report a problem or upload files

If you have found a problem with this lecture or would like to send us extra material, articles, exercises, etc., please use our ticket system to describe your request and upload the data.
Enter your e-mail into the 'Cc' field, and we will keep you updated with your request's status.

# Description

"Today I'm going to work with you on a new concept and that is the concept of what we call electric field. We spend the whole lecture on electric fields. If I have a -- a charge, I just choose Q, capital Q and plus at a particular location and at another location I have another charge little Q, I think of that as my test charge. And there is a separation between the two which is R. The unit vector from capital Q to li- little Q is this vector. And so now I know that the two charges if they were positive -- let's suppose that little Q is positive, they would repel each other. Little Q is negative they would attract each other.

And let this force be F and last time we introduced Coulomb's law that force equals little Q times capital Q times Coulomb's constant divided by R squared in the direction of R roof. The two have the same sign. It's in this direction. If they have opposite sign it's in the other direction. And now I introduce the idea of electric field for which we write the symbol capital E..."

Would you like to put a link to this lecture on your homepage?
Go ahead! Copy the HTML snippet !

1 Mr.Dione, January 23, 2010 at 1:52 a.m.:

2 Mr.Dione, January 23, 2010 at 1:54 a.m.: