Understanding Electric Flux and Calculating it in Different Directions

AI Thread Summary
The discussion focuses on calculating electric flux in different directions, specifically addressing confusion about the angle between vectors in a given problem. The participant is unsure if their calculations for part 1 are correct and questions the consistency of flux when the electric field is oriented in different directions. It is clarified that the flux can be determined using the dot product of the electric field and area vectors. For part 2, it is suggested that the flux is zero because the electric field is perpendicular to the area vector, resulting in a cosine of 90 degrees. The conversation emphasizes the importance of accurately determining angles in vector calculations for electric flux.
mr_coffee
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Hello everyone. I'm having troubles figuring out part 2 of this problem, and also can u see if i did part 1 correctly? To me it looks like the flux is going to be equal, if the E-field is in the i direction or in the z direction but somthing tells me how can the angle be the same in both cases? THe directions and my work is in the picture below, thanks.
http://img134.imageshack.us/img134/5505/lastscan1nc.jpg
 
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\int E \cdot dA = \ flux, with a uniform field it just becomes E dot A. All you have to do is the dot product of your two vectors for both of them. For aprt b) the angle between the two vectors is not 67.4.

Hint, teh first vector lies completely on the xy plane..
 
Ahh Thanks!
for part (b) it would be flux of 0 wouldn't it? because the E field is perpendicular to the Area vector which is cos(90) = 0. Right?
 
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