Electromagnetism and Energy - PowerPoint PPT Presentation

Loading...

PPT – Electromagnetism and Energy PowerPoint presentation | free to download - id: e48ba-ZDc1Z



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Electromagnetism and Energy

Description:

Electromagnetism and Energy. Causes and effects of. static and dynamic. electric & magnetic fields ... Boas Ch.4: partial differentiation (1-6) ... – PowerPoint PPT presentation

Number of Views:23
Avg rating:3.0/5.0
Slides: 13
Provided by: TheEvergr7
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Electromagnetism and Energy


1
Electromagnetism and Energy
  • Causes and effects of
  • static and dynamic
  • electric magnetic fields
  • Maxwell equations yield
  • electromagnetic waves
  • Electromagnetic energy
  • Thermal energy
  • heating, melting, boiling,
  • Potential energy
  • electrostatic, gravitational
  • Kinetic energy
  • Bernoulli equation

2
Electrodynamics Giancoli Ch.21-29 Physics of
Astronomy, winter week 6
  • Star Date
  • HW finish CO 3.6, magnitudes
  • Overview of EM Maxwells eqns
  • Minilectures
  • Derive EM wave equation and c
  • Next week write Interim Research Planning
    Report
  • Boas Ch.4 partial differentiation (1-6)
  • Week 8 Modern physics CO Ch.5 Interaction
    of light and matter

3
Causes and effects of E
  • Gauss E fields diverge from charges
  • Lorentz E fields can move charges
  • F q E

4
Causes and effects of B
  • Ampere B fields curl around currents
  • Lorentz B fields can bend moving charges
  • F q v x X IL x B

5
Changing fields create new fields!
  • Faraday Changing magnetic flux induces
    circulating electric field
  • Guess what a changing E field induces?

6
Changing E field creates B field!
  • Current piles charge onto capacitor
  • Magnetic field doesnt stop
  • Changing
  • ? displacement current

7
Maxwells equations
8
Maxwell eqns ? electromagnetic waves
  • Consider waves traveling in the x direction with
    frequency f w/2p
  • and wavelength l 2p/k
  • E(x,t)E0 sin (kx-wt) and
  • B(x,t)B0 sin (kx-wt)
  • Do these solve Faraday and Amperes laws?

9
Faraday Ampere
10
Sub in EE0 sin (kx-wt) and BB0 sin (kx-wt)
11
Speed of Maxwellian waves?
  • Ampere
  • B0/E0 m0 e0 v
  • Faraday
  • B0/E0 1/v

Eliminate B0/E0 and solve for v
e0 8.85 x 10-12 C2 N/m2
m0 4 p x 10-7 Tm/A
12
Maxwell equations ? Light
E(x,t)E0 sin (kx-wt) and B(x,t)B0 sin
(kx-wt) solve Faradays and Amperes
laws. Electromagnetic waves in vacuum have speed
c and energy/volume 1/2 e0 E2 B2 /(2m0 )
About PowerShow.com