Wed May 02, 2012 By:

how do we select a gaussian surface?

Expert Reply
Thu May 03, 2012

1. Choose the surface perpendicular to the field so that E and dA are parallel.

2. Choose the points on the surface to be a constant distance from the charge so that the magnitude of E does not vary.

3. If it is not possible to satisfy points (1) and (2), then choose the surface parallel to E so that E and dA are perpendicular and the dot product gives zero.

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