Does Huygens’ principle apply to so aktrdq+v;aof8)ebyf +.4f( e und waves? To water waves? Explain.

What is the evidence that light is yz- j:o 3rp5idenergy?

Why is light sometimes described as rays a) 7vh 2.go(vo2d jb arsy):yutnd sometimes as waves?

We can hear sounds around corners, but we cannot zjzw td5;n 9beg8x6y0see around corners; yet both sound and lightd; 90nez6 xbj8wg5zyt are waves. Explain the difference.

If Young’s double-slit experiment were submerged in water, how wou.qdd7ra+ugj 78gu 3tcld the fringe pattern be changed+cd8qg. 3 7a 7grjutud?

Monochromatic red light is incident on a double slit, and the interferen*n(-/lczpacxa-buo5h trqp0z, q 2 0owl , j)fce pattern is viewed on a scree har,j2 , oa 5/tnqzzlc-ob)l 0u(c0xq* fpwp-n some distance away. Explain how the fringe pattern would change if the red light source is replaced by a blue light source.

Two rays of light from the same source destructively interfere if thei *ksqq14.gr tbm5 kq(yww+ tgf mi2)y1r path lengths differ m1biqw.tmsf y(qw)2g415 +*gty qrkkby how much?

Why was the observatl,1)oo)2tsnndz5e,g 1vj yai ion of the double-slit interference pattern more convincing evidence fd2)ins l,5ajn1),t eyg ov1zo or the wave theory of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that forcng7)+: ktuix light waves. Discuss the sixgiu ct)k:7 +nmilarities and differences.

Why doesn’t the light from the two, , mqf v51whqco-p:oa headlights of a distant car produce an interfa5pqh,1- v: qo,mfcow erence pattern?

Suppose white light falls on the two slits of Fig. 24–7, buo y2fhll:8d x*t one slit is covered by a red filter (700 nm) and the otherhx *f8l:dlyo 2 by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it d lu9-oc-zs u(c(c(3w7 igguyis not broken down into colors as itw(oycig-(c(c z ug-d9ul3 s7 u is by a prism. Explain.

For both converging and diverging lenses, discuss how the qt8)7y5h( chw cojf7f3ygnz-l who;0focal length for red light difzf (y78o5qht ; c7f3wyhjowl -nh) gc0fers from that for violet light.

A ray of light is refracted through three differeir3dtvsj8cf1k 9- :e-gow ck:nt materials (Fig. 24–55). Rank the materials according to thv kfco s :j-d3:1w ketgr-i89ceir index of refraction, least to greatest.

Hold one hand close to your eye and focus ,v*a28 ul iu9df oc)206llzwzhy b. hdat (4sxon a distant light source through a narrow slit be6za b9(a fhlyzc u. ,lx8 wohlit2d2v*4)s0udtween two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single gflm40/36dylnq f +wyslit if the whole apparatus is immersed in (a) water, (b) a v0nmd/+f 6l3 ly yg4qwfacuum, instead of in air.

For diffraction by a single slit, what is the effect of increasing (a) the slit +d- .rr 6e,. t:pwmpeth ,yyriwidth, and (b) th:r , y6 eetwd,+rp-rp.y.hi mte wavelength?

What is the difference in the interferen41xqum)zu bil: 52bylce patterns formed (a) 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 slkiy;xmsh s -;3; uqaq/x/*0ciy ,j jluits, (b) closely 0s*is//k,xyuh aqxqu3c;l ;j ;jym i -spaced slits?

White light strikes (a) a diffraction grating, and (b) a prism. A rainbowk71o)tfr7:dhqbr e8 t 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 d87h7 q1k rtot)feb:r case? Explain.

For light consisting of wavelengkor ui +8mh klvcq9u i47* t2kihebx/ 93qdr:0ths between 400 nm and 700 nm, incident normally on a diffraction grating, for what hk23 d:rtx*k78 0 liv9or9hb4cu+/iiqm kqeu orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap bup 3xx(y 9b,6ukwjtpqy08t6i8o vks8 j bble and nxk,tjsy3 6wy qb u9ip k(0ovp8xt 6j88ot for a thick piece of glass, say?

When a compact disk (CD) is held at an angle in white wto5ganos+3 8 light, the reflected light is a fulls ng oo+t85aw3 spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closeecb(zwa./(v5-,k f ldcbv +m ar together farther from the center?

Some coated lenses appear greenish yellop )n;hi/5svou6bwg /d w when seen by reflected light. What wavelengths do you suppose the coating is designed to transmit completely?s/ n5vp/6w) hgdi;obu

A drop of oil on a pond appears bright atin,3xb4ob w 5 gz.(cgd its edges, where its thickness is much less than the wavelengths of visible light. What can you say about the index odgown x cizb53,g 4.b(f refraction of the oil?

What does polarization tell us about thimku m 5n9v/t,xjbgc-4/;62 xiaaqche nature of light?

Explain the advantage of polarized z09q; *r8qop7gcyn fg sunglasses over normal tinted sunglasses.

How can you tell if a pair * t: c,xkcr)xpof sunglasses is polarizing or not?

Two polarized sheets rotated at an angle of ;kr ( e xi6y+ komwu,w+tb**nc90$^{\circ}\,$ 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 nkz* eezexi 6-)o atmosphere?

If the Earth’s atmosphere were 50 times denser *k :a7 yu),,y mjmb)3jf-obw2kjqcuf 4pfia (than it is, would sunlight still be white, or woulk:yb2 qc)7uma p43af,wjmj-*(f,bok fy ) iujd it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart produces the fiftha9v)9 p;mzz-r qf z q(4rudv1l-order fringe at an v4 m;qq 9-arfd)z1l 9z(upzr v8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe)fpn nhlld;(bh2d m5hznh8j-q/: yw5 of 610 nm light is observed 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.3u 4fjli+wl- l Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern.f+lw -ji 3ul4l Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wa5w3cp am6:ffz j14ebcvelength 656 nm, falls on two very narrow slits 0.060 mm apart. How faefmwpa:1b65zf4cc j3 r 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 twayd: nzb6( 9qbo slits and produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m awaz9 b(yna6q:db y. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apart, how fo 72h91(sr ma rv/wkvhar apart are the second-o 29r 7(1vahwskvohrm/ rder fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experimqf,cv-)r 4tuhdvr 5a3 cd(cl-ent, it is found that blue light of wavelength 460 nm gives a second-oru,3crf(dhrl v cc- ta5dv -4q)der maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pn : 7b7y1f wy;htclwd2ass through two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relative to the “straight-through” direction wouyfwcn;t 7hlw21d:7yb ld there be little or no wave action?

Suppose a thin piece of glass is placed in front of the lower sli(h* som78v4e8a (w tyzqj1ae nt in Fig. 24–7 soat(7 * 81ezn8jmqa os(v4w yeh that the two waves enter 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-order maximum foip,-+7gjp f cn8 /a(s+d pskqlr light of wavelength 500 nm is located 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? s8i7p+-gsqd ,anfjk(lpp+c /    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm light. Finv)6u; 8ip uwjrd the distance between adjacent bright fringes on a scree8v) ;r w6uuijpn 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air6p( u8 /(rae :uewdcbw 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-slit appav pncmq6uq(aq .-j6 ( o anfw5c,(*urjratus 6fn.n* jaw a,oq (p rq6m-j u(vccqu(5illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximatet -y(d.dlj 1wgly, does the speed of red light (700 nm) exceed that of violet lighgw 1d -.jy(ltdt (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece /f s wp:n:owv4of glass 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 wavelength t;3dw/is epta lsosb4b0u5.d,9 4mq uaf tg0;s, $\lambda_1\;=\;450\;nm$ 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 0.044vc;)j(jw9g 4 el b5zdt hqq3g20 mm wide, what is the full angular width of thedvegb3q59t(;g q2 jh cw 4)jlz central diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit that 9pbm6 s 69 vsfo(wc0ltis $ 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 nd (eqo80*ko6 gul1 ptqm falls on 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 thxw6f9e,pa x rhb57 po8e width of the central maximum (in cm) ip ,5ofpx76 er8 w9hbxan the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle between t2 j 5q1gambpy4he first brighmpqy 5jgba2 14t fringes on either side of the central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m behxzep9 ( r32+zcwoz52a 3gtzqsind a 0.0348-mm-wide slit illuminated by 589-nm (w pzga9o rexz+z3q2 2z 5t3cslight?    cm

  When blue light of wavelenj(/)t fw5f1;qblvsum gth 440 nm falls on a single slit, the first dark bands on em(; 5b/1l)ftju qsvwfither side of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 4f4)mfn 1cdpa )dg(v6 e3o *c:/dctlzb 15 nm falls on a single slit, it creates a central diffraction peak that is 9.20 cm wide on a screen that ipcd*mlgf6 1d: f a3 dzov)(e)ct ncb/4s 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 al9nm rrp,s*8wide on a screen 1.50 m away, what will be the width of the diffraction ma,lm rn9a*p 8srximum for light of wavelength 420 nm?    cm

For a given waveleng83 s lo7ktbvurl 8gj:uk; .tg6th $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a second-order maximum when fallinr*fa lx v96 g u-qm*fsul1ecyk+2 n289 ryk-jwg on a grating who-l2a +8 6ux9* y*y92f vrrqn ukjlw- 1kfsgcemse 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 does a grating have i y 9pdq-jp/0v8ol z8 bl,zoc,mf the third-order occurs at an 18.0m,v-8 /d9 ozjoy,plbz l0cq8p$^{\circ}\,$ 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 light falling on a diffra-st.jo, l;(nmlwnn5xa;k ed3 ction grating is observed at a 15.5asl- mox5; njwd e(l,.knn3 t;$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating has 0j c:9i d:zm id;a :0cr-t4ju uhh1ibv$ 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 normalw) ) mch 16avhp,bh*chly on 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 sp8f-gebfo)6wo69 fc xvectral order that can be seen if a grating with 6000 lines per cm is illuminate 9e)v6wgoxfffo 8bc6-d with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen ole:,+ pud 4l )yg tnpr2ubn5m9n either side of the central maximum when whit9n4ltupp: y l )mrdg5n+, b2eue light 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 frw4 zw-2l/ rhlsom 410 nm to 750 nm falls on a grating withll s-zwwr4h2 / $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light e e94g0g)lq k qvi:fm6of 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 spectrumnauc;vl,q6:mbg*g v + lines are measured 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, )d3bg d odf(7js:wl7u. ysg7n what wavelength is most strongly reflected at the center of the ou (f: u77s)bl dwyojg.3n 7dsgdter 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 Exbfaw* /f3xd-/opbm, yample 24–8 if the glass plates are each 26.5 cm long? bf3 bp-*fwxo y/m,ad /    cm

  What is the smallest thickness of a soapbf(zdaerj4*3unb.9 1 4pdai zpr1qp ( 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 yel2u0 f6 eq8 kd3jgm:b uzuk;n7hlow ($\lambda\;=\;570\;mm$ 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’s rings )b* ,dynn,4tmkvsw1 : 7zrgyn(not counting the dark spot at the center) are observed when 4zwg) ,r ytn,n7y:1dsb* v kmn550-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 sepa/w4cuenx5z 6 erates one end of two pieces of optically flat glass, as in Fig. 24–33. When lwc4ez5unex/6 ight of wavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat tcgt.yhny -63 l vns:cks u)(w1on6k5 md22paglass surfaces if the glass is6csdg 2wonk2 yus pt:v6t3an(5n klh.yc1m- ) to appear bright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspecp1 dlj.i( 2aglted 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 alcohorssr4( /iv*y3vedm5 al $(n=1.36)$ 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 apparatus (Fig. 24–31) is immersed in a g(1lh,**c t.h;p1x vw ztbo cbliquid, the diameter of the eighth darkp;hc* .1v*b,b1zgc lx ottw( h ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the light entering an inbf xgb-8w20naq p5dz;terferometer if 644 bright fringes are countewn xdbpf b2ga0;8-zq5d when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferometr/zij n q zw1:-xj60rzer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. Whatirzw:-rjx0 nq /z 1j6z is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirr6tct-:6ef mtmu3-mf+ n roe/d or $M_1$ 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 anyydpd;x)ws*n1k17 h s interferometer (Fig. 24–59) passes through a small glass container containing a cavity 1.30 cm deep. When an1) s kh* 7;ywpyxdds1 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 wavelength of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are oriented at j2,jsusohk 9sn;f6a( uk -hx;65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle for an air–gla6uefi/zl0 ;hvss $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a dialz) k njz8o4tk8r8j e8mond submerged in water if the light is hittingz kk ze)jrt8 84ljn8o8 the diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them is a maximu.ivjrzuaer: v+ 7810bgw -mnem. At what angle should one of them be placed so that the intensity is subseque.1 vbvn0ru 8i aem7r+gezw j:-ntly reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so asqroxpj 2 ;k p)tut)j66 to reduce the intensity of the incident unpolarizeq;xo up2r 6kt) pjjt6)d light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented atgzhp* a /)9zrt 40$^{\circ}\,$ 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 (uchea :g3zxakt6o d*hi.n29 at 38.0$^{\circ}\,$ 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 reflecer z / )cnpw4igsi.+(ations off the surface 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 suriczp. 4 w/ (inra)gse+face.
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 successive Polaroid sheets, each of a7zmmn ;kq7+pe t r)8ewhose axis makes a 45)em;tqk7a8ze7n p m+ r$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 4xi5)e,)xc1hydz 3/uoah fs c$ 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 ref :;t .mt9q3q.dkz1tituc g:arlecting from mountains or airplanes can interfere with the direct signal frt3tc9 tk1.tzrq u: mgd.a:i q;om the 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 1e)d7uj or/co*rqzq/ *i,sws separate sources passes through a diffraction grating with eoqodri u /c qw,/ *szjr)*s71$ 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 passes through two nar (y)7wjbv bck*row slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wavelength produces its second-order f b7wby)*kjv(c ringe 1.33 mm closer to the central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operatini(o8do1c )sp+0s+ asycc5sfzipp b -2g at 102.1 MHz broadcasts from two identical antennae at the same elevation but 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 botcdf0s 2+pci1 b (sia 5z8ps+ysco)o-ph 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 wide,hvgk5 s .:i7.vj:nilvpu i+1 x and blows a whistle of frequency 750 Hz. Ignoring revixiv+svh5 l:i:u nj1g .7.pkflections, 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 on a single sli0fqo5chry m u8b/j)(cfl lr 2/t 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 across them. When kp cb/shy ,g4*normally incident 460-nm light is reflected from the wing, tc *,g kb4hys/phe 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 nhc3 .kw.7qf8 hb unwv;o second-order spec87k.f3 wnbw.hvc q;uhtrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white ;(fin z03uxowa 6t 7stlight produced by a diffraction grating always overlap. What waveiu6ttxs7 wn3a0 ;z f(olengths overlap exactly?

  When yellow sodium lightj6 -z(h:b, 3n bpkhmuu, $\lambda\;=\;$ 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 diffraction grating with annt4)5i+qkeh6nsf+tgd6 9zw qd the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists of two waveltw5e)+hid+ kgqq6 n6s4 9zntfengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ 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 materia-,fes--6 1ros zco7 ucd:uekil if a minimum of 150 nm thickness of it, when laid on glass,r-ieoodf -c1u,uc ks6 e7 -sz: is needed to reduce reflection to nearly zero when light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of vaqp.sp:r32z8 zbt *r ajriable wavelength is incident normally on a thin sheet of plastic film in air. The reflectt.2j3p * ar:sqz br8pzed 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-reflectigowp+9-6m t*y* xqft dve 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 (h snh);;si .;nscsjz 2ndpt;(non-zero) thickness for the air layer between two flat glass surfaces if the glass is to appear dark w;s);(nit dc;2 h;h.zj pnnssshen 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light eijiwyvg *0/zs.lu27- x) lfotransmitted through a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required for maxima and mine.* xlz7 io0f2 )lwv u-gyisj/ima. 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 is the Sun when light reflecting oy7pfj6 ev mg4f0 80fapff a smooth lake is polarized most stronglygfjayf pp6fe070mv 8 4?    $^{\circ}\,$

  At what angle should the axes of two Polaroids b-/ y4zsnzs3 *bh -qnfre placed so as to reduce the intensity of the incident unpolarized light by an additional factor (after the first Polaroid cuts it in half)nfr*y3h z-sbn 4qs/ z- of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets whosebx-eb 38mgodnon rfmb4g93+mn2 ( : xu transmission axes are at right angles. A third polarizer is placed between the first t3 mgrfeb9bn:8u(m 2bnmong3d4 x - +oxwo 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 t( twdm v;*q;s o4hmtyb 1ryku:22x(oiheir axes vertical, 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 through a slit of width 1.0 cm and is poinc0-tpfmu4 st:pg j(c1 ted at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves mg0s-j t(4fptc:u1cp 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 eac,e9 s7ao8n-g .kynghrlihky )1 /ce2hh placed 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 luj-(qtk a/ d7(q io2z2hlo*s$(n=1.34)$ 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 antennas26 /azsz jf)ll 9da+,7htrngc radiating 6.0-MHz radio waves in phase with each other. They are loca ,/as)nj dgz29cl7h fta6+zrl ted at points $S_1$ 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 two wavelengths, 420 nm and 65fj-1lp1 qkij 40 nm, enters a silicate flint glass equilateral prism (Fig. 24–58). kqi4 -11fj pjl
(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 surface and o+n fl+zwqa,o( ne 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