PHY 182 1st Edition Lecture 16Outline of Last Lecture I. Background to Gauss's LawII. Calculating Electric FluxOutline of Current Lecture I. Calculating Electric Fields with Gauss's LawII. Conductors in Electrostatic EquilibriumCurrent LectureCalculating Electric Fields with Gauss's Law- Setting the integral of electric field times surface area equal to the enclosed charge in a Gaussian surface divided by the electrostatic constant allows you to easily calculate electric field in a variety of geometric situations.- If you want to find the electric field inside of a rod (or other object), you should draw a Gaussian surface smaller than the rod.- If you want to find the electric field outside of the rod, you should draw a Gaussian surface that is larger than the rod.- Make sure that when you are writing Gauss's Law for a cylinder that you do not include the ends of the cylinder in the surface area expression.- When finding the electric field outside of a cylinder, you can model it as a line of charge. However if you are asked for the electric field of a cylinder, you must take its volume intoaccount.- When calculating the electric field for an infinite plane of charge, the area is simply equal to "2A". For the electric field close to a conductor (a situation discussed in the nextpart of these notes), the area is only "A" because there is no field on the inside of the plane.- When solving a Gauss's Law problem, the length (or any other associated quantity) of the Gaussian surface should cancel and thus should not be included in the final These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.expression. This is because the electric field should depend only on the original shape, not the Gaussian surface.Conductors in Electrostatic Equilibrium- Electrostatic equilibrium is a state in which the charges are at rest (which means that there is no net electric field).- Since the electric field in this situation is equal to zero, the enclosed charge must also be zero. This means that the charges reside on the surface. This occurs because the charges repel each other and the farthest they can get from one another is for them to all be at the surface of the object.- The electric field lines at the surface of a conductor are always perpendicular to the surface (because of this surface charge situation).- If there is a hole in the conductor, the electric field is still zero.- Michael Faraday was the first to discover the concept of electrostatic equilibrium. This occurs when you place a metal cage-like apparatus within an electric field and because of the conducting quality of the metal, the electric field within the cage is zero. This apparatus is known as a "Faraday cage".- If you are very close to a conductor, it will appear to be a flat line and you can model it as such. If you are very far from the conductor, you can model it as a point
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