2008SFinalSol - F. Phys;cs 202/ I 1;')'1 Sf/"; 1>...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Phys;cs 202/ Sf/"; 1>} 2°i?, 8 F . I E Name: r\ e ~ 1;')'1 Xa~ 1. [6 points] The cladding of an optical fiber has refractive index nc = 1.20. Light rays in the fiber core that make an angle of 30° or less with the fiber's central axis are reflected from the fiber core-cladding boundary without any loss in intensity; rays that make a larger angle with the axis decrease in intensity each time they reflect. What is the index of refraction of the fiber core? cladding, nc = 1.20 fiber core, nf central - - - - - - - - --- ~- ~ -3-00-- - - ~axis - - - - - -- - - -- e I e ::= 90° - f. W h e YI i> .::::;. 30: e ~ ec / fh e c ,.;f; C-4( Q."", / ~ to Y" +~+«. ( ; VI tel""~ { ,... ef/-e c f;o ~ (TI~) Q + +~e tl>vnJ~",y be:.tlA/ee'1r fhe f;ber Core a"J fA~ c(QJJ;j't'j. ec; -= 100 - 30° = 60°- Sin e =- nc C -' f\f n -:: nc - 1.20 - /J Q ~ - - -- - I S;'1 ec. s;~ tOo nf = I. 3 Cj. 1
Background image of page 1

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

View Full DocumentRight Arrow Icon
Name: f( e. ~ 2. [6 points] Two laser beams, both of wavelength A = 500 nm, are incident on a converging lens of focal length f = 25.0 cm and radius 5.0 cm. The beams are incident parallel to the central axis of the lens. One beam hits the center of the lens and and passes straight through, as shown. The other beam hits the lens offset from its center by 4.0 cm and is deflected by the lens; the deflected ray is not shown. A screen is 80.0 cm behind the lens. : scree : 4.0cm . : : ~ ! L 0 0 ; 80cm I 0 0 How far apart are the centers of the two laser spots on the screen? h -=. Lf.O CM fol' offset bect:/I"'1. T~ e Je .{Iec-f; D" aV'\fl-c 0 f fA;)'" 6elt--"1 if r;( = - Ph -:::: :11. d\ ::=. - O. I h raJia"j ( - 11~o ~ -= - 1. z 0 - f rr r~J:~. ..J' ) I h ; J b e ct: "'" h ; f J + h ~ .J" C r ~ ~ ,., IJ/ ;5 I' I ~ c. e: 0( J c ~ "'" b.7 ~"" ~"",o"",f L:J)(' -:=: (30C-fNI) +~f'\ ~ =:- - /2.1ct"1 dJ f J = I A + ~ X I = ( ~. 0 c,. .., - /2. q c ~ I 6 e '" ee" ',.t) d - g.1c~ between spots -. 2 !
Background image of page 2
Name: K e ~ ~- 3. [14 points] An object is placed a distance p = 0.50t in front of an ideal, thin converging lens of focal length t. (a) On the diagram below, carefully draw three rays from the upper tip of the object and use them to locate the corresponding image point. ; : I , --- I " ~ '"'" -- '0 -"--"""--~ F1 (b) What is the image distance i in terms of t (include correct algebraic sign)? I = , t- I J"=: I - I - - . - - -. f "fL T .; f fL -L= L..=.£. .i,=._~.£.- -:=. IJ-sof"l. - O.SIJf - - - - ~ f fl 'fJ- -I' /)-50.,[' - f -0 -s () i= -f (c) Is the image real or virtual? Please explain. rh~ I'/{l$ J",'f- ac/-"4/'y Cool"\~ I""",, f-h~ coi',.e.r,~"J.:f'l1 J"~ {)J- If" rhe. ; "",a,e. Image type: Vif'+C.I~( . : , (Continued on the next page.) 3
Background image of page 3

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

View Full DocumentRight Arrow Icon
f( -e r (d) What is the lateral magnification? Y'Y\= -~ = L- =- 2.1J f 0.50;(' m= 2.0 ! , i
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/01/2009 for the course PHYS 208 taught by Professor Amadeuri during the Spring '08 term at Cornell University (Engineering School).

Page1 / 18

2008SFinalSol - F. Phys;cs 202/ I 1;')'1 Sf/"; 1>...

This preview shows document pages 1 - 5. Sign up to view the full document.

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