1B24 Waves Optics and Acoustics Lecture 20 of 33 (UCL)

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ÂŽĂŤ òIĂŽ+Ă´Â?Ă°sĂ“mĂŽNĂŠzĂ°JĂŤÂŽĂŞ Ă”l*G4=@+>Â?- 71.M-/@+5tB:*G.151*£€‘- B:*Lv]* 06* Kp7M.19/DÂ?-/>/@+*G714=Kx.M-/AN4–-L714=9:@,*p¡U(+46Â?+46715ܼ_°Â?Âź3š/cÂŻb=Âż š/gJbü°Â?h_œ‘-/5 ;I9:.ÂŚD * Ke(_-/@N4=K -L0Y71.M-/@N58B:*G.158*a€‘- B/* 5 v_58ƒ+Ke( ˆŽ9:0–-/.84=51-L7M469:@HDÂ?- 2 Â?ÂŽ* ˆN0–-/@+*LvUKG4=.8K ƒ+0=-/. v?9:. *G0=0=46ˆN7M46K -/Ă–0 Ă•eO Radiation from a Dipole Source Ă€ Ă Ă‚ Ăƒ Ă Ă— Ă’ Ă˜ÂŁĂŽlѳÇ Ă?_ĂŠ#Ă”xÒ³ÊWĂ‹NΊĂ?›Ù Ăš"Ă›iĂœWĂ?Râ)äNÂœĂœ Ă™MĂšlĂ&#x; Ă Ă™ ĂĄlĂœ<Ăž .

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Fermat.mcd

1

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25/03/99 12:47

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Reflect1.mcd

2

25/03/99 12:51

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Refract4.mcd

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Mirage effects

COLD - large refractive index

HOT - small refractive index

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Ray passing from more to less optically dense region is refracted away from the normal.

Mirage1.mcd

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Mirage effects - star positions zenith apparent direction incident of star light ray from star

air layers of increasing refractive index (optical density)

ground level

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Mirage2.mcd

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