Exploring Electric Fields

On the previous page you worked with some simple examples of electric fields due to point charges.

Here is a program that simulates the electric field of a positive point charge. Move the mouse cursor around to see how the length and direction of the field arrow change. Also click the right mouse button to draw field lines, and then hit "E" or backspace or delete to erase the field lines. (Mac users: clover-click instead of right-click.)

This next example is the same, except the charge is negative. What about the field has changed?

Here the charge is also negative, but has a larger magnitude than the charge in the previous example. What about the field has changed?

What do you think the electric field would look like if there were two opposite charges some distance apart? Try it:

Here the charges have the same sign.

Here is a complicated case:

Here the positive charge is larger than the negative charge. Look to the right of the negative charge.

There is also an animated example of field lines that you can watch.