Does Huygens’ principle apply to soundl mn25be mt49*oaxv( vo)cuk0 waves? To water waves? Explain.

What is the evidence that light is *w2: sj gcl9)zwgy *:kdqafk4energy?

Why is light sometimes described as rays and sometimes as wyuc3(+)n g b onet70jvaves?

We can hear sounds aro )drq5y hi)j,zund corners, but we cannot see around corners; yet both sound and l r)i )d,yzhqj5ight are waves. Explain the difference.

If Young’s double-slit experiment were submerged9rj) b 9aaaor3 in water, how would the fringe pattern be ao)99rar3ja bchanged?

Monochromatic red light is incident on a double slit,kq* ipkiknesr.p)j 9/ u1l51d and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source ) i/k9pu.1nrpi1 dk jlkqe*s 5is replaced by a blue light source.

Two rays of light from the same source destru+1shqc+d *b hxh3oql (ctively interfere if their path lengths dil1x+dcq q* b h+o(h3shffer by how much?

Why was the observation of the double-slit interference pvtkrcxc6 -lh2-,;i .0vk xzucattern more convincing evidence for the wave theory of light than the obser;uvcxc .lc-k t2zikh0v-,rx6vation of diffraction?

Compare a double-slit experiment fov +;jzk iikh-0r sound waves to that for light waves. Discuss the similarities a-+z;k0kih vijnd differences.

Why doesn’t the light from the two headlights of a dis g/ :tvowdzw4 eaxq03c6rb,hn8ua:+ gtant car produce an interference pattcu4w30rx ze8 ga gdw/6n,:qh+b vaot:ern?

Suppose white light falls on the two slits of Fig. 24–7, but 8t(npd5vaeq7t5-keeak 98 dl one slit is covered by a red filter (700 nm) and the other by a blue filter (450 nm)8eked aql7n-tevtp85a9 (5dk. Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it is not brokezd- i jh d1.(4bkjpf6rat2f e9n down into colors as ikeif (hjr bd td 41-faz.p9j62t is by a prism. Explain.

For both converging and diverging len+inh )wa ,svm2ses, discuss how the focal length for red light differs from that for violethn+sw m)2, vai light.

A ray of light is refracnfw wd0 (9a:d)lss(y7adt 7 sjted through three different materials (Fig. 24–55). Rank twya t dfd)w7(9sjas0 l:d7n s(he materials according to their index of refraction, least to greatest.

Hold one hand close to your eye and focus on a distant light source through a naf09 ciklp7oe2k cy r(2rrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you seerp2i7cf(y90 elo ckk 2.

What happens to the diffraction pattern of a s6:4 cmksmv/a6bagi) gingle slit if the whole apparatus is imkgim c:4va)gs 66/ ambmersed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, 8u dd f78geuey0)maash,k3jprd55i8 what is the effect of increasing (a) the slit width, and (b) the wavelkad)udr 85esm503 upg jd y8hfi, e78aength?

What is the difference in the interference patterns formed (a) f 91 7oz5uzcf/jp+zf,bv (w rqby two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating,9bvu+w, h m-jducwgqhs9 b16 5 what is the advantage of (a) many slits, (b) closely spacq,1u5d6 s gwj- 9bh9bh+uwvmced slits?

White light strikes (a) a diffra,v 2k jcjv4db 86zkev;ction grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is theek62j 4vvj;kdc v8 zb, color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths betwhrg4/f f ijp*d9- 4 *qv;ew4 nm4olma:mhldk)een 400 nm and 700 nm, incident normally on a diffraction j hd)mg9i dfa/n o;l:vmrwkq p* *-me4l4f4h4 grating, for what 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 lis7ku0 5qwzwnxkj2w n46l0rm2 js3 b8eke a soap bubble and no5 0je73sr4 j bmlz2 086nwwxkuw2s nqkt for a thick piece of glass, say?

When a compact disk (CD) is held at an angle in white ligpp sou. 3:p3e w6or1yzht, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromat. op:p3z wr ps1u36yeoic light was used?

Why are Newton’s rings (Fig. 24–31) closer together fartx 5p-hsu 6d4jvher from the center?

Some coated lenses appear greenish yellow whene4*. mon4a0fwx l w40y g0qgcq seen by reflected light. What wavelengths do you suppose the coating is designed to tranqg0o 0*e4 wg0a m.f n4qc4ywxlsmit completely?

A drop of oil on a pond appears bright at its edges, where itspjpa; te9s4w 4 thickness is much less than the wavelengths of visible light. What can you say about the i p eptj44;wa9sndex of refraction of the oil?

What does polarization tell us about the nat+qe( 7lnxb; hwure of light?

Explain the advantage of polarized sunglasco schmkh7, /;ho5c3 ca-uw.7, go mcsses over normal tinted sunglasses.

How can you tell if a 7k/eh5r zeihto,rj94+zhc g ; pair of sunglasses is polarizing or not?

Two polarized sheets rotated at an angle ofz3 nwy;q:tk:zs y-q(zvi3 oj- 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 atm7iw 5s 5ha v5;q4uzrvaosphere?

If the Earth’s atmosphere were 50 times denser than it is,wkjxafd)a1 zj -a 26g- would sunlight still be white, or would it be some othedaj--kaajfwgz x162 ) r color?

  Monochromatic light falling on two slits 0.016 mm aparu e7wv: czd 65*rr/ank*v,hrit produces the fifth-order fringe at an 8.8a c6ri /v57* dkr*zunewhr,:v$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed at an anglev irsx;3up4;bee bszo); d( .o 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. Succes srbxx+/5cy p uv)lfh1: oj)*fsive fringes on a screen 5.00 m away are 6.5 cm apart near the center of th*f5)jo1 rfcup+sbvx: x)/ y hle pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, wbubdcs hb;t a6 1t hg-4-pf:)hith a wavelength 656 nm, falls on two very narrow slits 0.0su)ab -phh c1btg6h4:db-tf ;60 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 ::ff7,;cjdy ;uilt4eth 6 gd cqb)/crand produces an interference pattern in which the fourth-order fringe is 38 mm from the central fringr:flcb)c6g7;tce;u jy /i,dt:qh fd4e on a screen 2.0 m away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes th/*rfxx +pt1x nrough two slits 0.58 mm apart, how far apart are the second-order f/f *nxptx 1r+xringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blueuly1 85clq(v o2n e;sm light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light2n(o;ecyq lv1mu5l 8 s would have a minimum at the same location?    nm

Water waves having parallel crest m+ /z(c8g5aq oq+qjsls 2.5 cm apart pass through two openings 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relativeamg8 +o 5 qljqz/c(q+s to the “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass is placed in fro0 ejc-z zmedrxg*f) ,;nt of the lower slit in Fig. 24–7 so that the two waxer e)0m;gc- ,z*fdjz ves 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 for light of g2gd,7 ik6k.*pv2 s(r-ddwbgm8ragl 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 thi gbmr*s g k(g2dkadd2rvgi8 ,p-l7w. 6s light be located?    mm

  Two narrow slits separated by 1.0 mp*e+lj-d jhkszlw72ib /u +s*vaw+o(m are illuminated by 544 nm light. Find the distance between adjacent bright fringes on a screen 5.0 m from the slits pa+o lwu+ s7js-v*+kdz j* hiel(2wb/.    mm

  Light of wavelength 480 nm in air falls oy3)sc( ls4sti7bq7nzxxcdbsyg 0gv 9rz (61+n 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 apparacd 6)3p2(h y vdo+bxeotus illuminated by 640-npv3xoeo d) (dh2c 6b+ym 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, approximately, does the speed of red ligl9ugu;c. f lp,o8 agpd89d jv7ht (700 nm) exceed that of violet light (400 nm) in silicate flint glass? (See Fig. 24–149, l vpgpa7.du 8uc9gj;lf 8od.)    %

  A light beam strikes a piece of glass at a 60.00ij:rqo7/ 1*g3 wgk;i )awrtfx $^{\circ}\,$ 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 coq0vh :7 yyen+c2z +/ / aguif4qep.nvfntaining two wavelengths, $\lambda_1\;=\;450\;nm$ 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 0.04*vzvfl2(k h1r40 mm wide, what is the full angular width of the kh z2vlfvr*(1 central diffraction peak?    $^{\circ}\,$

  Monochromatic light fall* / gig x4if:rkq5pq1bs on a slit that is $ 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 fkj5 chsco;ex*cz- ) mj.v 4-xoalls 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-ncn yavn19/2 dfm light. What is the width of the central maxifnd/n 92yca v1mum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. ra;7k)upjx gs7oh9y5 If the angle between the first bright fringes on either side of the cu7ypj9 go);r xa5kh7sentral maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m behinik*vw2/.xxy,dq1hzx8m duta d e4,+ id a 0.0348-mm-wide slit illuminated b* zu,hqvdmkex2t ay4x+1i,i/d .8dxwy 589-nm light?    cm

  When blue light of waveleng1zk *6w r)huorth 440 nm falls on a single slit, the first dark bands on either side of center are separated bkou1h )*r6 zrwy 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on am 2gpe :,+oxwcn*lpy, single slit, it creates a central diffraction peak that is 9.20 cm wide on o, ,+mpwyl e 2xn:*pcga 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 4yk9-q:dpd1yr.jjrw l *u7 qd+.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for light of wdp 9jjw*.d-q :y1+qrk d luyr7avelength 420 nm?    cm

For a given wavelengthuoixz8 9 ) a9lxn:bl wxff3dil0g8*m. $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a f24a+6bog d08o:/b s tt/myvrov*ndj second-order maximum when falling on a grating w+ / y /6: mftrjb0tod2anv8ovsgob4d*hose 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 havcxn04 bxt v,zwd 16i0:bfvia5e if the third-order occurs at an 106z1 a vtf:bb,v0ndw4x5cxi i 8.0$^{\circ}\,$ 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 light falling on a diffraction grating is9,p-ynm.bbgvg wdq-w rd,;: y observed at a 15.gywpwdn-dq9;.,r-yb b ,v g: m5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating hasi 9f7bk2hx,r7 at jox6 $ 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 on a* xfrzccek5g4 c0+l 6l $9700-line/cm$ 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 thah+1vfq 3gq ga0t can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser3qha01+ gfgvq light? Assume normal incidence.   

  Two (and only two) full s..ox5gs vdu2f pectral orders can be seen on either side of the central maximum when white light is sent through a diffraction grating. What is guxo2 5dv .sf.the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 753 w q2x)c,w5jvsv u.ou0 nm falls on a grating with uvv cw ) .uqsjw5o2,3x$8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochromatic light of a k)v5b *y6k4axnfr,z ansic8: znown 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 measu6 2czbj,oz6 jvred 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, what wavelength is most stronbt mbgza+we+-vu1n2 jo 9b 1t,gly reflected at the center of the outer surface whenbb29t-n je mu +zwo 1,+1gbatv illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 if5ahl39bakz s : the glass plates are each 26.5 cm lob zsk:h9 la35ang?    cm

  What is the smallest th unwpac(iw+umy 8v6w x+:00 esickness 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 yellol(dq/bgm2f8 u hcq/n.w ($\lambda\;=\;570\;mm$ 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 zss51wu tp(4 w(not counting the dark spot at the center) are observed when 550-nm light falls 1st(p54ws zuw 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 two pieces of optica g.hbw t-c/. ra:bga5klly flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with onek .ga:.hwr /cbag-5bt at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air layer ljb ;b2afk03orv n 3f-be between two flat glass surfaces if the glass is to appear bright when 450-nm light is;k 0aj 2 rvo-3nbfbfl3 incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, s9e9cr kat27x0afd +hyuspected 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 alcoholmw7h8q yqv 7t4wo g18i $(n=1.36)$ 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 i v 7ud(6sl3djrmmersed in a liquid, the diameter of the eighth dark ring decreases from rs6ud j3 7d(vl2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the light entering an interferometer ik 9uxw0a6jdez:;1 qob86saz6h at0gdr )l+ kaf 644 bright fringes are counte uro:l d9dhtka6zba0swqa x8z+kj e 60)1ga;6d when the movable mirror moves 0.225 mm?    nm

  A micrometer is connectep go+(wnh b5 n;(9f/h gwkbumy2o3 vn6d to the movable mirror of an interferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the emptovbhugy32w np k /(59( of+mn;w6gbhny micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm.    $\mu m$

  How far must the mirrhv)jnw:s1xi:i h+f.p :ft:5yf. )bi -mw gpmgor $M_1$ 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 interferometewj dg5;;f) melg;wj d:jdz5c:r (Fig. 24–59) 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 wavelength of 610 nm. Calculate the index of refraction of the gas, assuming that the interferometer is inf gw;c j:;)5z5jjd;elmgwd:d vacuum. $n_{gas}$

  

  Two polarizers are oriented * ck2k.; aehkg)+iaqt at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s angle fp38fyu ryh g8s m08,dbor an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light is hittinhh/ +68u6jtx lvzdny)g tn xdytz/jvu h+l68) h6he diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing nc 62o-o ts4wfthrough them is a maximum. At what angle should one of them be placed so4oc f6twon s-2 that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to dmdff8; jn6 j*7fmhs, reduce the intensity of th jnmd;mh,6* djfffs 87e incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriefcylawl/n +utxn( f43g; *8bc nted at 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 at 38.04jvioucyn fv+0ng++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 reflect t:p,voc7h( a q8usw.tions 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 surface. tw (o.sv8pau hq,t7: c
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 P a;p8gl siwux:hsmmhc n8 029*)m7nnjolaroid sheets, each of whose axis makes a :ucn)a80 snhhmn8g*w jm72s;l9xpmi 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength *llyw s*7xq+f$ 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 reflecting atcy0 v+7gom.xd)x7r from mountains or airplanes can interfere with the direct stxoy) x 7a.mg+c07 rvdignal from 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 seo1ryh o;mq -nss0; 1qbparate sources passes through a diffraction grating with nm1rh;so-syq0qob 1;$ 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 w 8xd/wvftqze5n44 +e 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 th45f+vnwz e/qxted4 8 we wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1cu-kh,+hs2vg6g gu-o 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, perpvg2,6u hgcu hs-og- +kendicular 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 frwsm6 dg fj-d :lt1l-y4a7op,rom an outside doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outsir:fd-,-y7pjw s gdal t41om6l de the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single slit of wi i*r02 uvqu b .jg(*m0di3grjcdth 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 da2e5lld wl ad,4x :,pacross them. When normally incident 460-nmepda, x,4l:ald 5d2 wl light is reflected from the wing, the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centimet2aym:gumuy/hf :if 9ic(d +0 yup8 jb3er must a grating have if there is to be no second-order spectrum for any visih/3u(bg:+:0faucm j p m8yyuif29 dyible wavelength?   $ lines/cm$

Show that the second- and third-orvbcav4zu u*18 : ,o :plpfhxi)der spectra of white light produced by a diffraction grating always overlap.u: 1v, 4b8a)o*iv zxucpfh:l p What wavelengths overlap exactly?

  When yellow sodium light,8v2y2ogtvo9 x $\lambda\;=\;$ 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 diffractgb)t9v)qyfa2m efb6* elm +:v ion grating with and the pattern is viewed on a screen 2.5 m from the grating. The incident light beam consists bmlvq)ef:+y 9e2fg*a) mvbt 6 of 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 ja7j6 ( yzgz3(q+ ugttof a clear material if a minimum of 150 nm thickness of it, when laid on glass, is needed totzt6(gqgj (z aj+u3y7 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 variable wavelength iscq8mz3 dyoe4gl+1f * l)zu-vg incident normally on a thin sheet of plastic film y14eum) z+3-o fg zclqg8v*dlin 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-reflective co0tx-2 zgne; zdy,; dvkr :yy)iating $(n=1.38)$ 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-zero) thickness for the air layer betwet;su r,j .axz8nes9e4en two flat glass surfaces if the glass is to appear dark when 640-nm light is incident normally? 4e;xz 8sujn,9sart.e    nm
What if the glass is to appear bright?    nm

Suppose you viewed the a 4/gfa wp4g*jlight transmitted 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 minima. Consider all possible values of inde*4 f/gwaj4a pgx 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 reflectif. edv4q3d ;s9-w ohxpr /0myvng off a smooth lake is polarized most strongl0h3m4y;o dv xq9wsr p ./d-fvey?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so a:mnzni t5tnm gor:p1*v9 dap e ;f8sc.3p, eb.s to reduce the intensity of the incident unpolarized light by an *i9:p8p z1:pdat .eb3nn em,gnot cs r.f;mv5additional factor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets whose transmission axes are at r2ke/ph/7vm(zt a gqf:ight angles. A third polarizer is placed between the first two so that its axis ma(e7/va2pmfq kz gh /:tkes 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 vern1 r5ydfg*i;ilm)*)o r: d rfetical, 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 pointey9s,u :;ma)eem ns) d6u f ybv9;e+imfd at the Moon, which is approximately 380,000 km fro9 9bmmasd yu:u ey)esv);ie;ff+n ,m6m 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 uij9s( y oy)o gekk075each 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 :r duib t89dnqftzbe :x)k: *($(n=1.34)$ 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-MHf ;fzf)0:h(p4j djvpr kpa;rd2jmd *4 ) xnz/pz radio waves in phase with each other. They are/ j(kn2pp;0m )*x;hd p rfr)jzf:vdazf j4d4p located 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 conti,r4i( xnfk )gt; 7zfuaining two wavelengths, 420 nm and 650 nm, enters a silicate flint glass e( itx,4;krf7in fuzg)quilateral prism (Fig. 24–58).
(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 surfa i5:hl/s7 30s:qbopxakp3zzsce 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