1 / 9

Announcements

Announcements. Homework for tomorrow… (Ch. 26, Probs. 22 & 50) CQ 8: 2nC/cm 2 26.12: a) 0 b) –(4.1 x 10 3 N/C) ihat 26.42: Lim_{z<<R} -> K Qz / R 3 , Lim_{z>>R} -> K Q / z 2 Office hours… MTWRF 9-10 am Tutorial Learning Center (TLC) hours: MW 8-5 pm T 8-6 pm

umay
Download Presentation

Announcements

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. Announcements • Homework for tomorrow… (Ch. 26, Probs. 22 & 50) CQ 8: 2nC/cm2 26.12: a) 0 b) –(4.1 x 103 N/C)ihat 26.42: Lim_{z<<R} -> KQz/R3 , Lim_{z>>R} -> KQ/z2 • Office hours… MTWRF 9-10 am • Tutorial Learning Center (TLC) hours: MW 8-5 pm T 8-6 pm R 8-11 am, 2-5 pm F 8-2 pm

  2. Chapter 26 The Electric Field (Motion of a dipole in an E-field)

  3. Last time… • E-field of a infiniteplane of charge.. • E-field of a sphere (of radius R) of charge.. • E-field of a parallel-plate capacitor..

  4. 26.7: Motion of a Dipole in an E-field Recall the polarization force between a q’ed & neutral object… • The qpolarizes the neutral object, creating an induced electric dipole. • The q then exerts an attractive force on the near end of the dipole that is slightly stronger than the repulsive force on the far end. - - - - - - - + - - + - - - + - - + - + - - + +

  5. Motion of a Dipole in an E-field Consider a dipole in a uniform electric field… Notice: • There is NO net force on a dipole in a uniform E-field. • The dipole experiences a torque… + -

  6. Motion of a Dipole in an E-field Consider a dipole in a uniform electric field… Notice: • There is NO net force on a dipole in a uniform E-field. • The dipole experiences a torque… + -

  7. Motion of a Dipole in an E-field Consider a dipole in a non-uniform electric field… Notice: • The dipole 1st rotates until aligned with the E-field. • The net force on a dipole is toward the direction of the strongest field. • A dipole will experience a net force toward any charged object.

  8. Quiz Question 1 An electrically neutral dipole is placed in an external field. In which situation(s) is the net force on the dipole zero? • (a) • (c) • (b) and (d) • (a) and (c) • (c) and (d) • Some other combination.

  9. i.e. 26.11: The force on a H2O molecule. H2O has a permanent dipole moment of magnitude 6.2 x 10-30 Cm. A water molecule is located 10 nm from a Na+ ion in a saltwater solution. What force does the ion exert on the H2O molecule?

More Related