1 / 8

Quizzes 3

Quizzes 3. A cube with 1.40 m edges is oriented as shown in the figure. Suppose the cube sits in a uniform electric field of 10 i ? What is the magnitude of the flux through the whole cube? What is the magnitude of the flux through the top side? How many sides have nonzero flux?.

jerrod
Download Presentation

Quizzes 3

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Quizzes 3 A cube with 1.40 m edges is oriented as shown in the figure • Suppose the cube sits in a uniform electric field of 10i ? • What is the magnitude of the flux through the whole cube? • What is the magnitude of the flux through the top side? • How many sides have nonzero flux? • q/eo D) q/6eo • q/4eo • 0 • 2 D) 1 • 4 • 0

  2. Applying Gauss’s Law Charge in a long triangular channel What is flux out of one side? charge q • Can be used to determine total flux through a surface in simple cases • Must have a great deal of symmetry to use easily

  3. Applying Gauss’s Law r • Draw a cylinder with the desired radius inside the cylindrical charge L R • Infinite cylinder radius R charge density  • What is the electric field inside and outside the cylinder? • Electric Field will point directly out from the axis • No flux through end surfaces

  4. Applying Gauss’s Law r • Draw a cylinder with the desired radius outside the cylindrical charge L R • Infinite cylinder radius R charge density  • What is the electric field inside and outside the cylinder? • Electric Field will point directly out from the center • No flux through endcaps

  5. Applying Gauss’s Law r • Draw a Gaussian surface inside the sphere of radius r Sphere volume: V = 4a3/3 Sphere area: A = 4a2 R • Sphere radius R charge density . What is E-field inside? • What is the magnitude of the electric field inside the sphere at radius r? • R3/30r2 • r2/30R • C) R/30 D) r/30

  6. Conductors in Equilbirum • A conductor has charges that can move freely • In equilibrium the charges are not moving • Therefore, there are no electric fields in a conductor in equilibrium = 0 = 0 • The interior of a conductor never has any charge in it • Charge on a conductor is always on the surface

  7. Electric Fields near Conductors • Add a gaussian pillbox that penetrates the surface Area A Surface charge  • No electric field inside the conductor • Electric field outside cannot be tangential – must be perpendicular • Electric field points directly out from (or in to) conductor

  8. Conductors shield charges • Draw a Gaussian surface • No electric field – no charge • Inner charge is hidden – except Charge -q Charge +q No net charge • What is electric field outside the spherical conductor? Charge q • Charge +q on outside to compensate • Charge distributed uniformly

More Related