Does Huygens’ principle apply to sound waves? To mxxz7-bw*sc )1nctgp1) ; ltu7 rw (ymwater waves? Explain.

What is the evidence that light is energv 3;3u7yg /mmsv6pb cqy?

Why is light sometimes described as rays and sometimes as wa0rj da3fk,cw2k nf79 5 le.gjtves?

We can hear sounds around corners, but we cannot see around corners; yet both 9h(;nxatuiw9q s2(a hsound whin a(s9t(x9a2 ;qhu and light are waves. Explain the difference.

If Young’s double-slit experiment were submerged in water, how would-i +tcsm c+ ubl e)x68s4z krpm)(d0hm the fringe patter0 klbu8+mm)+dzmphx rc(6)4-e cisst n be changed?

Monochromatic red light is incident on a double slitz8waz1p+v e 5y, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replace +zp 1zeyav5w8d by a blue light source.

Two rays of light from the same source destructively interfere if thex 9.f,x3gh 6j eoxi-e* +pjgbzir path lengths differ ef*jzegox6i9x -x+ p b h3,g.jby how much?

Why was the observation of the double-slit interference pattergkf;q t;: jfn ,g59bwvn more convincing evidence for the wave theory of light than the observation of din 9:t 5gk,qw;;vgbjff ffraction?

Compare a double-slit experiment for sound waves to that for light ntg;s roj94;qm/c b.hwaves. Discuss the similarities and differens9b;c o tj/ rh.gq;n4mces.

Why doesn’t the light from the two headlights of a distant car produce an i86hdbqc 9j8vanterference paqj b 8chdv9a68ttern?

Suppose white light falls on the two slits of Fig. 24–7, but one slit is coverp11aa ylg)9 eted by a red filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the screegyep l)191 atan.

When white light passes through a flat piece of window glass, it is not brok38eu8go6u3ito1sj 4z 8 (ttemasg o3oen down into colors as it is by a pu8 i831es o emgjttg(48at 63ozo3uosrism. Explain.

For both converging and diverging lenses, discuss ari(fi/w wz(erp/4qqk +(p+c how the focal length for red light differs from that for violet ligh+iwz /qar/(f(q kp(c4wie rp+t.

A ray of light is refracted through three d5ho:)xjv+n:co +fcva ifferent materials (Fig. 24–55). Rank the materials according to their index of rev v++fco : ):jx5achonfraction, least to greatest.

Hold one hand close to your09u yqhr mdn.( eye and focus on a distant light source through a narrow slit between two fingers. (Adjust your fingers to obtain (u0rdh .9mqny the best pattern.) Describe the pattern that you see.

What happens to the difmu uhy1/p*uj*fraction pattern of a single slit if the whole apparatus is i m1yp/uuj**uhmmersed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, what is the effect of increasing (a) th8 i58serlbtl-n; ej gt6jwl24b* aj1 ze slit width, and (b) the wave2jlb4*elz-sje85;tlj t ra nw 1 gbi86length?

What is the difference in the interference patterns formed (a,mz3dt 7nca 1j ow4.ci,me6 ux) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slit4n uvbkaj4t9v 4bq(0 0zc)wkps, (b) closely qw9a)4j4 vtk v0k(c zu 0nb4pbspaced slits?

White light strikes (a) a diffraction grati1a9mx e*0v ,wng3 gpia/ih*7lhwmj c+ng, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top of the rainbow in each wh gi0l/ 1g*jmi* 7h vnc9,x3wpmaa+e case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, incident norzep l)8sayiw,t(w8 n.mally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on t) pwsly .ei(w88nt,zahe slit spacing?

Why are interference f)2 fz7+zcvegtovf.h 4ry0 iu0ringes noticeable only for a thin film like a soap bubble a )iy zgc0e0+4vu. ohf7vrft z2nd not for a thick piece of glass, say?

When a compact disk (CD) is held at an angl/3sr :ylb xyg1oq,y(qe in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. What would youq,:xl1ry b/ygsq o (y3 expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer together fae qhv+0q g(w/rrther from the center?

Some coated lenses appear greenish yellow when seen by reflected light. What wavycbv pb *rxprt4j 6c+,dlhae-z+)/p.elengths do you suppose the coating is designed to transmi/lzvc rbh,cx6tja++pp e d. by4)-*rpt completely?

A drop of oil on a pond appb*ci6d0 c zgl sx0 mf;78kucw5ears bright at its edges, where its thickness is much less than the wavelengths of visible light. What can ym;lsk6 ucxzdcw50 g8f* 7icb 0ou say about the index of refraction of the oil?

What does polarization tell us about the nature of lightz y6 upz4(mw+x?

Explain the advantage of polariz21.tn)i ema fmed sunglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is polariz x8t8vp9cf6 q3rjoez/ing or not?

Two polarized sheets rofv9- s cdbo:0ftated at an angle of 90$^{\circ}\,$ with respect to each other will not let any light through. Three polarized sheets, each rotated at an angle of 45$^{\circ}\,$ with respect to each other, will let some light through. What will happen to unpolarized light if you align four polarized sheets, each rotated at an angle of 30$^{\circ}\,$ with respect to the one in front of it?

What would be the color of the sky if the Earth had no atmospgb,8y5; ksqvg1kxb/ there?

If the Earth’s atmosphere were olh-)cvjxc lx,6 (r0u50 times denser than it is, would sunlight still be whxx lc6,)-0jhulcor( vite, or would it be some other color?

  Monochromatic light falling5xnbc+9o wyy5,)wvn3 zq 9v0qn zh;ic on two slits 0.016 mm apart produces the fifth-order fri ,qnzq35)z bv wcn0y9 vo +9ynicxh5;wnge at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observe taerw50upq 43ys zk69d at an angle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light falls on two very narrow slits 0.048 mm apart. Successiv)3 *r0hf,pviit5a7y3edcuar e fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. Determine the wy3ieaapu7 r ,3)* dhi5tvrfc0avelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a Hen ds yux(0+t9z-Ne laser, with a wavelength 656 nm, falls on 9t+ uyn0xds(ztwo very narrow slits 0.060 mm apart. How far apart are the fringes in the center of the pattern on a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits and produces an interferrim a kq2rl/zxf4/c l7+)g+ xhence pattern in which the fourth-order fringe is 38 qf a7 +hmg+kr2lxciz)/4xrl/ mm from the central fringe on a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apart,.hp yjb)3iegc2n3 ;gv how far apart are the second-order fringes for these two wavelengths on a screen 1.0 m away?h3g 2.jnvpbe)c;gy 3i    mm

  In a double-slit experiment, it 369 iwhtg9ihy is found that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at ty9tw hg9 h6i3ihe same location?    nm

Water waves having parallel crests 2.5 cm apart pass through two openings 5.0 qa/s:i nndzf7x9bym(ym51 ,z cm apart in a board. At a point 2.0 m beyond the board, at what angledan 5 7fmzymn9b/q1ysi: (xz, relative to the “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass i:xjogq/ 7iewwr4*nq3f o 7nkb*z91vis placed in front of the lower slit in Fig. 24–7 so that the two waves enterno7fjv b43wio n qq/**: exwg1zk97ri the slits 180$^{\circ}\,$ out of phase (Fig. 24–57). Describe in detail the interference pattern on the screen.
24-7
24-57

  In a double-slit experiment, the third-xx,06 b uib)wrorder maximum for light of wavelength 500 nm is locate xrb0bw)i,6xud 12 mm from the central bright spot on a screen 1.6 m from the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot will the second-order maximum of this light be located?    mm

  Two narrow slits separate3*kkb7p5p3y1 e ys.xmj t)oiz d by 1.0 mm are illuminated by 544 nm light. Find the distance between adjacent bright fringez m ) s3oki5yp.7tj13yxk*ebp s on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 n+ 7lnt)lk.9banij/ nrm in air falls on two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers one slit of a double-slbxb 0-o;ur-utf74 pps it apparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness o;4b x urt7bpfp-os0-uf the plastic?    nm

  By what percent, approximately, does the speed of red ligh6,snnni o9al-uu3 qu( t (700 nm) exceed that of violet light (400 nm) in silicn6qu(ai,snl u u n-o93ate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of gl2m3rjhyo xc(xo*w(. sass at a 60.00$^{\circ}\,$ incident angle. The beam contains two wavelengths, 450.0 nm and 700.0 nm, for which the index of refraction of the glass is 1.4820 and 1.4742, respectively. What is the angle between the two refracted beams?    $^{\circ}\,$

  A parallel beam of light containing two waveleng0l: o 2fb2wha;rzat0w ths, $\lambda_1\;=\;450\;nm$ and $\lambda_2\;=\;650\;nm$, enters the silicate flint glass of an equilateral prism as shown in Fig. 24–58. At what angle does each beam leave the prism (give angle with normal to the face)?
$\theta_{d1}$    $^{\circ}\,$ from the normal
$\theta_{d2}$    $^{\circ}\,$ from the normal

  If 580-nm light falls on a slit 0.0440 ef xfn zpll k4yd889wah57d7 3mm wide, what is the full angular width of tz7nfl8 yp4l5h9dxe k 3afw7 d8he central diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit that is :t1a ery tn8.xc:nwewbw f 7+.$ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls oniux62slq/ 9zl vp5ipzoc zmt 0kvpu9.3)7 5lw a slit that is $ 3.20\times10^{ -3}\;mm$ wide. Estimate how far the first brightish diffraction fringe is from the strong central maximum if the screen is 10.0 m away.    m

  A single slit 1.0 mm wide is illuminated by 450-nm light. What is the g 5z7l do 6q/lxhgrl6ba8l(+s width of the central maximum (in cm) in the diffraction pattern on a drblla(/h 76 llgog 6+q5s8xz screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls oln; )fhcb e1,a,( (ykc vov2 1pzihot(n a slit. If the angle between the first bright fringes on hh( ( ,tz1bo1a( oc;),l nikevvp2cfyeither side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak j7g7l ux.wr+gj im95don a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-nm9+d5gljurwx g7.mj7 i light?    cm

  When blue light of wavelength 440 nm falls on a single slit, th xp*9jq j/u9;-j d7shyginf;oe first dark bands on either side 7;/ fq-yij*9nu hjs x;g9dpjoof center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on a single slit, it creati-/bs,p o3 jjfph d-s +5vqtu(es a central diffbiu o 5t-fp+ss(3q,jp /vj-dhraction peak that is 9.20 cm wide on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffraction maximum is 4.0 cm wide m65wp8, d;-brb tn gbhon a screen 1.50 m away, what will be b; hw8-g pt5b6mn db,rthe width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengthacrjamsv+4 +llt- x* , $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light prodjq-db,erc:r nw h.+ 6 qeiow..uce a second-order maximum when falling on a - rowcn:. +q6i .drw.eqejbh, grating whose slits are $1.45 \times10^{-3 }\;cm$ apart?    $^{\circ}\,$

  A $3500-line/cm$ grating produces a third-order fringe at a 28.0$^{\circ}\,$ angle. What wavelength of light is being used?    nm

  How many lines per centimeter kc600expqrm3 +a d gb x,w kezn-a -qy5e+4u8gdoes a grating have if the third-order occurs at an 18+ geg4pbqa08+nax, 5w z--e630rkec ky mduqx.0$^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

  A grating has $8300\;lines/cm$. How many complete spectral orders can be seen (400 nm to 700 nm) when it is illuminated by white light?   

  The first-order line of 589-nm li85: x6(-wvrl gz0pwiug,d vd mght falling on a diffraction grating is observed v dw(dw0rv5luxi6g8 ,z :-pgmat a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating hl)07xeow*y 4qn,l y kjas $ 6.0\times10^{ 5}\;lines/m$. Find the angular spread in the second-order spectrum between red light of wavelength $ 7.0\times10^{-7 }\;m$ and blue light of wavelength $ 4.5\times10^{-7 }\;m$.    $^{\circ}\,$

  Light falling normally om5k6,wgt43f 0 4y 8-k7earvnuamren3 qe 6pa xn a $9700-line/cm$ grating is revealed to contain three lines in the first-order spectrum at angles of 31.2$^{\circ}\,$, 36.4$^{\circ}\,$, and 47.5$^{\circ}\,$. What wavelengths are these?
$\lambda_{31.2}$    nm
$\lambda_{36.4}$    nm
$\lambda_{47.5}$    nm

  What is the highest spectral order +w p- 5u,0l v9sexk2xq 3ugyycthat can be seen if a grating with 6000 lines per cm is illuminated with 633-nm lase 3ug-k5v90p 2usl+,wycxeqy x r light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on either sig5d-c 3 lc4h;)jh8v3vhf(yq rhmjhi/de of the central maximum when white lightgfh cj/3lh(vh;hy c5j-)4rvdmqih8 3 is sent through a diffraction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from bs07ztf:r/ldr/ryx 3b7b q3q9 g za+ a410 nm to 750 nm falls on a grating with7zfs q3arlx:tzyb70/ 9 gd q b/rb+r3a $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromnqz,y )-/jn0k+i mzgs atic light of a known wavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 21.5$^{\circ}\,$ to the incident beam. How many lines per meter are there on the grating?    $ \times10^{ 5}\;lines/m$

  Two first-order spectrum lines are measurecyrx, (gs )b2yns u.0bd by a $9500-line/cm$ spectroscope at angles, on each side of center, of +26$^{\circ}\,$ 38$^\prime$,+41$^{\circ}\,$ 08$^\prime$ and -26$^{\circ}\,$48$^\prime$,-41$^{\circ}\,$ 19$^\prime$. What are the wavelengths?
$\lambda_{26.72^{\circ}}\;=\;$    nm
$\lambda_{41.23^{\circ}}\;=\;$    nm

  If a soap bubble is 120 nm thick, w/q8,*x lxc/vzi;jz wo76g qwzhat wavelength is most strongly reflected at the center ofj wzz8z*wo6,x v /xc q7igql/; the outer surface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Ex 20rcme evfc;3ample 24–8 if the glass plates are each 26.5 c ecem23f0vc ;rm long?    cm

  What is the smallest thi;z +*(pa-c7 zdpuxy csckness of a soap film $(n\;=\;1.42)$ that would appear black if illuminated with 480-nm light? Assume there is air on both sides of the soap film. $t_min$    nm

  A lens appears greenish ye7 jwt4 pbe82vjllow ($\lambda\;=\;570\;mm$ is strongest) when white light reflects from it. What minimum thickness of coating $(n=1.25)$ do you think is used on such a glass $(n=1.52)$ lens, and why? $t_{min}$    nm

  A total of 31 bright and 31 dark Newton’semo(j/lj4e i om3l8g/ rings (not counting the dark spot at the center) are observed whenli el/e8( om/3o4j mgj 550-nm light falls normally on a planoconvex lens resting on a flat glass surface (Fig. 24–31). How much thicker is the center than the edges?    $\mu m$

  A fine metal foil separates one end of twox/+a gk*md0 tczi9g i5 pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). H9dxi/0+ *tzkg g 5acimow thick is the foil?    $\mu m$

  How thick (minimum) should the ai+fw7-sl c whm2q6: ebp2osd4m r layer be between two flat glass surfaces if the glass is to apw:ef7 clq 26-m db+wmpssh42opear bright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspec 1kqz73l:euzdf(6s s*:ab cidted of being a stolen diamond $(n=2.42)$ is submerged in oil of refractive index 1.43 and illuminated by unpolarized light. It is found that the reflected light is completely polarized at an angle of 59$^{\circ}\,$. Is it diamond? ----待选择----yesno 

  A thin film of alcohoz- g05,eylla ul $(n=1.36)$ lies on a flat glass plate $(n=1.51)$. When monochromatic light, whose wavelength can be changed, is incident normally, the reflected light is a minimum for $\lambda\;=\;512\;nm$ and a maximum for $\lambda\;=\;640\;nm$ What is the minimum thickness of the film?    nm

  When a Newton’s ring appa 2q7:w hj aeo67g,shppz:z: sbratus (Fig. 24–31) is immersed in a liquid, the diameter of the eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive indexj 2b,psh7w s:p zz qo:7hea6g: of the liquid?   

  What is the wavelength of the light env2d9r/- 7fp )y)tqtir2 f rd 2r c:arjyn3bl*otering an interferometer if 644 bright fringes are counted wb3t-vyp2rylr:or /r i29dt nf) rdaqc)7*jf2hen the movable mirror moves 0.225 mm?    nm

  A micrometer is conne+vw/wmch lv+ ;cted to the movable mirror of an interferometer. When the microme+ c wvl/mv;hw+ter is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirror ;kt)yeb7c: :)eswq zu $M_1$ in a Michelson interferometer be moved if 850 fringes of 589-nm light are to pass by a reference line?    mm

  One of the beams of an interferometer (Fig. 2ne09kf 7klw3l cvdau 9oiv x24t7wz614–59) passes through a small glass container containing a cavity 1.30 cm deep. When a gas is allowed to slowly fill the container, a total of 236 dark fringes are counted to move past a reference line. The light used has a wavelekxiv vo lc49a fdt179 nk20l ezw6wu37ngth of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orient9p d6 -gwb xkgsr:uf18ed at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle fx 7ry+/wj g -wha8msekl+v 9(oor an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged 1d2qf*gj*xk zin water if the light is hitting the diamzf12*d* gqxkj ond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the linbxeer2zjsm(om g7 m ;2 *h4hh.l3i;f ght passing through them is a maximum. At what angle should one of them be placed so tg3hm br*;.ojen (s7 mmx4 ;zhhel2f2 ihat the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Pp ycb2q*3 ltk.m. ul lg;fiy3-olaroids be placed so as to reduce the intensity of the incident unpol.-lgi u3*yqp3k2;f.tbmc ly larized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at ca3tj .n 0,jga40$^{\circ}\,$ to each other and plane-polarized light is incident on them. If only 15% of the light gets through both of them, what was the initial polarization direction of the incident light?    $^{\circ}\,$

  Two polarizers are oriented at 38.k5qa48kuj/9 7aascb ppl 6 8je0$^{\circ}\,$ to one another. Light polarized at a 19.0$^{\circ}\,$ angle to each polarizer passes through both. What percent reduction in intensity takes place?    %

  What would Brewster’s angle be for reflections off the surfacyaijsl g4rb03v y:b,x6 vpd-)wz m9 5ke of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above the surface. ) ma5k,pxz3 bwjd9 l-:y6i4b v0yrsgv
If the light is coming from water to air, $\theta_{p}$    $^{\circ}\,$For the refraction at the critical angle from water to air $\theta_c$   $^{\circ}$ If the light is coming from air to water $\theta_p'$   $^{\circ}$

  Unpolarized light passes through five suh640xnz fv6 vsccessive Polaroid sheets, each of whose axis make0h 4zfx6sv n6vs a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength yyeq,: pq(pl m 43-fvb$ 5.0\times10^{7 }\;m$ passes through two parallel slits and falls on a screen 4.0 m away. Adjacent bright bands of the interference pattern are 2.0 cm apart.
(a) Find the distance between the slits.    mm
(b) The same two slits are next illuminated by light of a different wavelength, and the fifth-order minimum for this light occurs at the same point on the screen as the fourth-order minimum for the previous light. What is the wavelength of the second source of light? $\lambda_2$    $ \times10^{-7 }\;m$

  Television and radio waves reflecdn30n )on) h0 pc,v)yoief+qyz8sh .bting from mountains or airplanes can interfere with the direct signal from tyndo)8n es3vo fby)zpn+,c 0h. ih0q)he station.
(a) What kind of interference will occur when 75-MHz television signals arrive at a receiver directly from a distant station, and are reflected from a nearby airplane 118 m directly above the receiver? Assume $\frac{1}{2}\;\lambda$ change in phase of the signal upon reflection.  ----待选择----constructivedestructive 
(b) What kind of interference will occur if the plane is 22 m closer to the receiver?  ----待选择----constructivedestructive 

  Red light from three separate sources passes through a diffraction htkfd ;(d8tih0 ia / ixp ryss+xa,21*grating with ihadidy8 (1 ;frt 2/p ishskx+a ,x0t*$ 3.00\times10^{5 }\;lines/m.$ The wavelengths of the three lines are $ 6.56\times10^{-7 }\;m$ (hydrogen), $ 6.50\times10^{ -7}\;m$ (neon), and $6.97 \times10^{ -7}\;m$ (argon). Calculate the angles for the first-order diffraction lines of each of these sources. $\theta_{h}$    $^{\circ}\,$ $\theta_{n}$    $^{\circ}\,$ $\theta_{a}$    $^{\circ}\,$

  Light of wavelength 590 nm passesya:+rrs7pe( h,en d k, through two narrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wavelength produces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. What is the wavelength of the unk s7ke: rd e,ayrhn+p(,nown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identp.v3j4hhzof9fnxyho0 6)i xi4 bn (y/ical antennae at the same elevation bufz6 )i x9/(j obnipxhn v o4.yh3f4y0ht separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizontally in both directions. If the midline is taken as 0$^{\circ}\,$, at what other angle(s) $\theta$ is a maximum signal detected? A minimum signal? Assume all measurements are made much farther than 8.0 m from the antenna towers.

  A teacher stands well back from an outside doorway 0.88 m wy9xqxmh:b* *wide, and blows a whistle of frequency 750 Hz. Ignoring q:*hy xbwx 9m*reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls o:jg,gnr ;yb s;n a single slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel lines acrossgh .- y7 xin/1ko)+3ztljal (; ke)6 cqjcdtey them. When normally incident 460-nm light is reflected from thej .1 oxk hd;-yz c/et3cykl))+lja(ngei7t q6 wing, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimeter must a grating have if there is to be nb2k* yd8kalu y/v t1;yo second-order spectrumv 8u d1y /kykblt2a*y; for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light prodiu vzkj( 9c;w8r ui,6iuced by a diffraction grating always overlap. What wavelengths overlap exarcz; (vjii iw9ku u8,6ctly?

  When yellow sodium ligh+ypm i7x7 4czqx l*t/et, $\lambda\;=\;$ falls on a diffraction grating, its first-order peak on a screen 60.0 cm away falls 3.32 cm from the central peak. Another source produces a line 3.71 cm from the central peak. What is the wavelength of the new source? How many $lines/cm$ are on the grating?
   nm
  $ lines/cm$

  Light is incident on a s7y7 tdpwg6 idwm;6 t+)fe5kz7( qzjidiffraction grating with and the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists g;s)e wmf d(6+tt q7ip7kwz 76 diyj5zof two wavelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a mini(ue n 0fm1fmfi3ah( b 9t hg.rhgn*;t8mum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to near; hh9f1 bu emt0t fi((8mnhr*fg 3ga.nly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of va:0q ;a zssl8tgriable wavelength is incident normally on a thin sheet of plastic film i:ta8 l; ssqg0zn air. The reflected light is a minimum only for $\lambda\;=\;512nm$ and $\lambda\;=\;640nm$ in the visible spectrum. What is the thickness of the film $(n=1.58)$? [Hint: Assume successive values of m.]    nm

  Compare the minimum thickness needed for an anti-r8/d/g ojga d:r( id7kgsdqb; )eflective coating $(n=1.38)$ applied to a glass lens in order to eliminate
(a) blue (450 nm),    nm
(b) red (700 nm) reflections for light at normal incidence.    nm

  What is the minimum (non-zerf(yf8+: tbb;( dnu -9w zvbxino) thickness for the air layer between two flat glass surfaces if the ;b8tb+d: nffy(-bivzx (nwu9 glass is to appear dark when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light t 2jgsth,n 150rv(hhln ransmitted through a thin film layered on a flat piece of glass. Draw a diagram, similar to2,hjvsh nrg1h tn0 (l5 Fig. 24–30 or 24–36, and describe the conditions required for maxima and minima. Consider all possible values of index of refraction. Discuss the relative size of the minima compared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon i34g421 loab uuwvmo tjh0acy 8n);y-l s the Sun when light reflecting off a smooth lake is polarized most str4hyw )-0 g ao;21couy8lutvjml 4bn3aongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to rezbk h.lr4v 7- nvi1k9educe the intensity of the incident unpolarized light by an additional factor (after thez97n-v4k.hr1il kb ve first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets 1yy7q.jddr8qismxnjg5*09l whose transmission axes are at right angle sqm8i.0nx9djyd1r *7gy5 j qls. A third polarizer is placed between the first two so that its axis makes a 62$^{\circ}\,$ angle with the axis of the first polarizer.
(a) What fraction of the incident light intensity is transmitted?    $I_0$
(b) What if the third polarizer is in front of the other two?

Four polarizers are placed in succession with their axes vej/+ 3cnk;qvyak c74uro3 1d tortical, at 30$^{\circ}\,$ to the vertical, at 60$^{\circ}\,$ to the vertical, and at 90° to the vertical.
(a) Calculate what fraction of the incident unpolarized light is transmitted by the four polarizers.
(b) Can the transmitted light be decreased by removing one of the polarizers? If so, which one?
(c) Can the transmitted light intensity be extinguished by removing polarizers? If so, which one(s)?

  A laser beam passes thvln ,:81 )oxuwiw ow3crough a slit of width 1.0 cm and is pointed at the Moon, which is approximately 38 wxwli13):8,uov nw co0,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the width of the beam when it reaches the Moon.    km

  A series of polarizers are each placedtypxupk + ( 3*(gav, yuh8b,iq at a 10$^{\circ}\,$ interval from the previous polarizer. Unpolarized light is incident on this series of polarizers. How many polarizers does the light have to go through before it is $\frac{1}{4}$ of its original intensity?   

  A thin film of soap q3for04 hjwk .ptow2 4$(n=1.34)$ coats a piece of flat glass $(n=1.52)$ .How thick is the film if it reflects 643-nm red light most strongly when illuminated normally by white light?    nm

  Consider two antennas radiating 6.0-MHz radio wa5lzn7iq f svtm;7 +zz,xgi/)0o afyog y;2 bv:ves in phase with each other. They are located at point,f xfg;mn; 27zb5gy)y toz+v/ ova :s0 q7lziis $S_1$ and $S_2$, separated by a distance $d\;=\;175m$, Fig. 24–61. What are the first three points on the y axis where there will be destructive interference? (Destructive interference in this case means that a radio receiver placed at that point would pick up no signal).    m    m    m

  A parallel beam of light containing 1htw 54oylg ( yp2nfx2two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (Fig. 24–5f5yg4x1(2 twplhn yo28).
(a) What is the angle between the two beams leaving the prism?    $^{\circ}\,$
(b) Repeat part (a) for a diffraction grating with    $^{\circ}\,$

  A Lucite planoconvex lens has one flat sur5gwgc u6 ,7(k3fufy-fszmk x+face and one with $R\;=\;18.4\,cm$ It is used to view an object, located 66.0 cm away from the lens, which is a mixture of red and yellow. The index of refraction of the Lucite is 1.5106 for red light and 1.5226 for yellow light. What are the locations of the red and yellow images formed by the lens? [Hint: See Section 23–10.]
$d_{i-red}$    cm
$d_{i-yellow}$    cm