Problem Statement A long hollow soda straw has a total charge Q uniformity distributed on the straw's surface. Using Gauss's law find:
a) The electric field at a point inside the straw.
b) The electric field at a point outside the surface of the straw, located a distance r from the center of the straw, but is still quite close to the straw's surface (so that the straw appears to be quite long in each direction compared to the distance the point is from from the straw).
Visual Representation
• Draw a sketch of the charge distribution.
• Determine the symmetry of its electric field. Choose and draw a Gaussian surface with the same symmetry.
• Be sure every part of the Gaussian surface is either tangent to or perpendicular to the electric field.
Mathematical Representation
• Write the expression for Gauss's law. Determine the amount of charge inclosed Evaluate the surface integral
• Solve for the electric field. Check that your result has correct units and is reasonable. +