24
Electromagnetism PHYS20141 nutshell summary 1 Paul.Campbell-3@manchester.ac.uk Schuster 4-11

PHYS20141 nutshell summary 1 - University of Manchester

  • Upload
    others

  • View
    1

  • Download
    0

Embed Size (px)

Citation preview

ElectromagnetismPHYS20141 nutshell summary 1

[email protected]

Schuster 4-11

2

0/1. Revision and

mathematical Preliminaries

0.1 Previous “Electricity & Magnetism”

1.1 Scalars & vectors

1.2.1 GRAD, 1.2.2 DIV, 1.2.3 CURL

1.2.4 Vector calculus

1.2.5 Integral theorems

1.2.6 Co-ordinate systems

1.3 Dirac delta

1.4 Laplace’s and Poisson’s equations

3

Revision

- DIV, GRAD & CURL

- Laplacian

- Vector identities

- Divergence & Stokes’ theorems

(*) There is a “formula sheet” in the first set of notes.You are expected to know the formulae in Cartesiancoordinates, but will not be expected to remember orprove those for cylindrical and spherical polarcoordinates.

Grad

4

Divergence

5

+ ve -ve

Eg v = xi + yj Eg v = -xi - yj

Curl

6

CURL is out of the page

Eg v = -yi + xj

Vector identities

7

Divergence theorem

8

Stokes theorem

9

Normal into

the page

10

Old and new…

- Polar coordinates

- Dirac delta “function”

- Laplace’s equation & Poisson’s equation

- Uniqueness theorem for Poisson’s equation

- General solution to Poisson’s equation

3D curvilinear coordinates

We will often wish to use 3D curvilinear

coordinate systems such as cylindrical polar

coordinate.

The most important point is that the formulae

for GRAD, DIV, CURL and the LAPLACIAN are

modified because the basis vectors depend

on position.

11

12

Cylindrical & Spherical Polars

Cylindrical coordinates Spherical coordinates (MATHS!!)

Divergence - cylindrical polars

- you will not be expected to remember these

13

Dirac delta

14

This, the Dirac delta, provides our route to

mathematically defining the density of an

infinitely small object with has finite

charge (or current).

Gaussian function

15

Point particles

Eg. Charge density of a set of point

particles with charge qi and positions ri

NB. delta has dimensions, (length)-n

16

Important identities…

17

18

Old and new…

- Polar coordinates

- Dirac delta “function”

- Laplace’s equation & Poisson’s equation

- Uniqueness theorem for Poisson’s equation

- General solution to Poisson’s equation

19

Blended Learning…

- (Previous courses and notes)

- Supporting videos

- The notes and recommended texts

- Critically, the example sheets (for your tutorial) and the online exercises

- The tutorial

- Synchronous session and discussions

20

BL notes & books;

21

BL notes & books;

22

BL Blackboard examples;

23

BL Tutorial examples;

24

BL synchronous session;

Before your tutorial we will meet and in

that (weekly) session, address common

queries that have been raised and review

the examples..

[email protected]