PHY 2049: Physics II - PowerPoint PPT Presentation

About This Presentation
Title:

PHY 2049: Physics II

Description:

PHY 2049: Physics II. Coulomb's law: Two kinds of charges, positive and negative, ... in an electron that sits on a cesium site and neutralizes it, which way does the ... – PowerPoint PPT presentation

Number of Views:56
Avg rating:3.0/5.0
Slides: 18
Provided by: phys7
Learn more at: http://www.phys.ufl.edu
Category:
Tags: phy | cesium | physics | repel | talp

less

Transcript and Presenter's Notes

Title: PHY 2049: Physics II


1
(No Transcript)
2
PHY 2049 Physics II
  • Coulombs law
  • Two kinds of charges, positive and negative,
    unlike attract, like repel.
  • Electrons and Protons
  • q 1.602 x 10-19 C
  • Current I dq/dt 1 Amp. 1 C/s
  • Add forces as vectors

3
PHY 2049 Physics II
  • A rule
  • Try to calculate the force magnitude by ignoring
    the signs of charges. Then assign the direction
    by looking at the signs.
  • Never do both (using the charge signs in the
    calculation of the force and then assign the
    direction).

4
PHY 2049 Physics II
  • q1 2Q
  • q2 - 2Q
  • q3 -4Q
  • E at origin

5
Phy 2049 Physics II trial run
-0.344N, -0.218N, 212.38º
  • In Fig. at right, the particles have charges q1
    -q2 300 nC and q3 -q4 200 nC, and distance
    a 4.0 cm.
  • What is the direction of the force on particle 4?
  • A. B.
  • C. D.



6
PHY 2049 Physics II
3,1,2
  • Balls are touched and then separated. Rank them
    by
  • Charge left
  • Magnitude of Force before
  • After
  • Charge transferred

7
PHY 2049 Physics II
TALP Take a look Problem
  • Force on the center charge 6kq2/d2
  • Direction -x, 180º,

d
8
PHY 2049 Physics II
  • q1 q4 Q q2 q3 q
  • what is Q/q so that the force on 1 is zero
  • All charges same sign. There is no solution.
  • Q and q different sign. There is a possible
    solution.
  • Is the answer the same if the force on 3 is to be
    zero

9
PHY 2049 Physics II
  • What is the force on the central chlorine ion?
  • Suppose that we put in an electron that sits on a
    cesium site and neutralizes it, which way does
    the Chlorine move?

10
PHY 2049 Physics II
environment
  • Electric Field
  • Force F qE
  • E k ? r qi/ri2

Test charge
11
(No Transcript)
12
  • Electric field lines denote direction
  • Their density represents magnitude
  • They do not cross

13
Physics II
14
PHY 2049 Physics II
15
PHY 2049 Physics II
  • Induction and charge transfer on contact
  • Forces summed as vectors
  • Electric fields

16
PHY 2049 Physics II
17
Physics II
  • Potentials add like numbers
Write a Comment
User Comments (0)
About PowerShow.com