2303_-_Spr_2011_-_Week_5_-_Maxwell's_Equations_&_Light

2303_-_Spr_2011_-_Week_5_-_Maxwell's_Equations_&_Lig...

Info iconThis preview shows pages 1–18. Sign up to view the full content.

View Full Document Right Arrow Icon
Satellite image of the straits of Bosporus using visible and infrared. 11
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Week 5-1: Maxwell’s Homework Review Review Wave Equation Speed of Light Next: Gauss’ Law Ampere's Law Gauss’ Law for magnetism Faraday's Law Maxwell’s displacement current Reading: Chapter 34 22
Background image of page 2
The Wave Equation (Ch. 14)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The Wave Equation (Optional) Use F = ma , with & = M / L the linear mass density of the rope.
Background image of page 4
Speed of Light To measure the speed of light, we must measure distance and time for light travel. Section 35.1 1667: Galileo hilltop experiment: 3 km Response time ~ 0.2 s too slow 5
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Speed of Light 1675: Roemer studies timing of eclipse of moons of Jupiter with Earth at point A. Then at point C, 6 months later, eclipse is 16.6 minutes late. Estimated c ≈ 2.3∙108 m/s View of Jupiter and the 4 Galilean moons through a small 6
Background image of page 6
Speed of Light 1849: Fizeau Find time for returning beam to pass through next cog Found c ~ 3.1 × 108 m/s 7
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Speed of Light 1860: Foucault - vary mirror rotation speed - no signal unless mirror rotates 1/8 turn in Δ T c = 2.98∙108 m/s 8
Background image of page 8
Speed of Light To measure the speed of light, we need to measure distance and time. We can measure distance to 4 parts in 109 We can measure time to 1 part in 1013 Time measurements are convenient, distance measurements are difficult Therefore, we now define the speed of light c = 299,792,458 m/s, Use lasers and time measurements with the definition of c to measure distances 9
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Extras
Background image of page 10
Moving Pulse y = f(x - x0) same shape moved a distance x0 to the right: x y x = x 0 0 Given a function y = f(x) : x y 0 Let x0 = vt Then y = f(x - vt) describes the same shape moving to the right with speed v. x y x = 0 v UIUC 11
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Week 5-2: Maxwell’s Equations Gauss’ Law Ampere's Law Gauss’ Law for magnetism Faraday's Law Maxwell’s displacement current Reading: Chapter 34.1, 34.2, 34 appendix 12 12 circuit
Background image of page 12
Gauss's Law: The net electric flux through any closed surface is proportional to the charge enclosed by that surface. See chapter 23 13
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Ampere's Law: Calculation of B (Esp. in cases of high symmetry) See chapter 29 14
Background image of page 14