Warming up on Electric Fields

This assignment is due before 9 AM, Wednesday, September 13th, 2000.

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The following three questions refer to the material you were to read in preparation to the lesson. Questions one and two require you to write a three or four sentence response. Number three is a multiple choice question. Click in the appropriate circle.

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1.

Point charges are located at the points (-3, 0), (0, 0), and (3, 0). The outer two are positive, while the one at the origin is negative. To calculate the electric field at the point (0, 3), we need "r hat" vectors that point from each point charge towards the point of interest. Please find the three "r hat"'s.



2.

Let's say you are holding two tennis balls (one in each hand) and let's say these balls each have a charge Q. Estimate the maximum value of Q so that the balls do not repel each other so hard that you can't hold on to them.





3.

An insulator is a material that ...

a) Cannot feel an electrical force.

b) Is not penetrated by electric fields.

c) Cannot carry an electric charge.

d) All of the above.

e) None of the above.

Below is a space for your thoughts, including general comments about today's assignment. What was hard or confusing (or cool)? What would you like to spend extra time on in class? Do you see how this subject fits in with the others we have discussed?




You may change your mind as often as you wish. When you are satisfied with your responses click the SUBMIT button.

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