Chapter 36a - Chapter 36: Diffraction ! ! ! ! Youngs...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Ch. 36: Diffraction - Part A 1 December 7, 2009 1 Chapter 36: Diffraction ! Young’s interference experiment. ! Examples of interference. ! Two HITT questions. ! Single-slit diffraction.
Background image of page 1

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

View Full DocumentRight Arrow Icon
Ch. 36: Diffraction - Part A 2 December 7, 2009 2 Young’s Interference Experiment ! Thomas Young (1773-1829), an English polymath, proved in 1801 that light is a wave.
Background image of page 2
Ch. 36: Diffraction - Part A 3 December 7, 2009 3 Young’s Interference Experiment ! The interference pattern is determined by the path length difference L of the rays reaching a point P on the screen. ! d is the distance between the two slits. ! Angle θ specifies the location of the bright and dark fringes on the screen. ! Need to relate θ , L , d and λ . ! L is the distance S 1 to b . ! Assume that the screen distance D is much greater than d , thus r 1 and r 2 are parallel. sin θ = L d sin λλ = Ld
Background image of page 3

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

View Full DocumentRight Arrow Icon
Ch. 36: Diffraction - Part A 4 December 7, 2009 4 Young’s Interference Experiment sin θ λλ = Ld integer (maxima) integer+0.5 (minima) sin λ = dm sin ( 0.5 ) =+ for m=0,1,2,. .. ! Maxima, or bright fringes (bands): ! Minima, or dark fringes (bands): for m=0,1,2,. .. ! θ =0, m=0, central maximum.
Background image of page 4
Ch. 36: Diffraction - Part A 5 December 7, 2009 5 Intensity in Double-Slit Interference ! If the two waves interfering at point P have E’s: 2 1 4c o s 2 φ = o II 2 sin π φθ λ = d 10 sin ω = EE t 20 sin( ) =+ t and where ! The two waves combine at point P with intensity:
Background image of page 5

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

View Full DocumentRight Arrow Icon
Ch. 36: Diffraction - Part A 6 December 7, 2009 6 Interference Example !
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 18

Chapter 36a - Chapter 36: Diffraction ! ! ! ! Youngs...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online