Does Huygens’ principle apply th.i68 c(ipda7 z hwqkh5 u-3ayo sound waves? To water waves? Explain.

What is the evidence that light is ene +med3fkf.pr (r( wi9v)0c ufprgy?

Why is light sometimes described as rays and sometimes as waz oxj.gq.a k1*wpf:/nves?

We can hear sounds around corners,a3 cx81z *g/k +ddwzahzu )ji-ooi9d 1 but we cannot see around corners; yet both sound and light *o d d1ozak3whuj9 cigid/a1z)+x 8-z are waves. Explain the difference.

If Young’s double-slit experiment were submerged /mh :5 tw4any b/2j)/bwpjc inin water, how would the fringe pattern be chanb5tw/:hbwnya jp / mn42jc/i) ged?

Monochromatic red light is incident on a3li-y t t/lx8f double slit, and the interference pattern is viewed o 8iylx /lftt3-n a screen 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 sourcei;w -7qj 5vlijr7x+bm destructively interfere if their path lengths differ7j7iqlwx;mi vbjr 5-+ by how much?

Why was the observation of the double-sljg+ aqcq:vu 30it interference pattern more convincing evidence for the wave theoryv ja +c0g:u3qq of light than the observation of diffraction?

Compare a double-slit experiment for sound waves to that for liartaix *dh8zdir /eb* 0ev*.:ght waves. Discuss the similaritzi*e /aa 0*8h e.*trvddr:ix bies and differences.

Why doesn’t the light from the two headlights of a distant car produce an interfts g. ivrv;55sez/ub.erence ;5/ ti5z u.svrvbg.es pattern?

Suppose white light f e41tb.+emq zzalls on the two slits of Fig. 24–7, but one slit is covered by a red filter (700 nm) and the other by a blue filter (450 nm). Describe the pattern on the1zm+4be q zt.e screen.

When white light passes through a f ypd 2fm4-mb/:7f+er bs;dzs( ,isozblat piece of window glass, it is not broken down into colors as itepb,szm4sb f;z2mi7:b+ dy fodr-s/ ( is by a prism. Explain.

For both converging and diverging lenses, discuss how the focal length t3m lna2( diq1for red light differs fromt1i (nlqdm3 2a that for violet light.

A ray of light is refracted through three different materials (Fig. 24– 2cjxo*g r+ama cq2.v+55). Rank the materials according to their index of refraction, leas+xqocc2g* jvar+.m2 at to greatest.

Hold one hand close to your eye and focus on a j ) bcjq7ipip sc1vtxz;437b9sii 64zdt (md-distant light source through a narrow slit between two fingers. (Adjust your fingers to obtain the best pattern.) Describe the patterpcbitv-;q41z 37(st)4isp76 jb 9x mid zijdcn that you see.

What happens to the diffraction pattern of a single slit if the whole apparatu b*)crsc(jb4a s is immersed in (a) water, (b) a vacuum, instead of in bbsca4 ) rc(j*air.

For diffraction by a single slit, what is the effect of increasing (a) t )jw:okccq*hq4 9e5qh he slit width, and (b) :cojhqq )w94 e kq5c*hthe wavelength?

What is the difference in the interference patterns fo k:w b,y zydgta u:x:h)ig68 ed*8a8uxrmed (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 xs, uyv r1,o4q q.tc/txw79raslits, (b) closely srq.xq y97/,svutc1o , 4wratxpaced slits?

White light strikes (a) a diffraction grating, l/fl-g s;y9 ucand (b) a prism. A rainbow appears on a wall just below the direction of the horizontal inf-uyl9l g/c s;cident beam in each case. What is the color of the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm and 700 nm, incide x7og2c(fle a.nt normally on a diffraction grating, for what orders (if any) would tf 2. ale7(cgoxhere be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes notil fv;/:nf 6 kj5s.izoiceable only for a thin film like a soap bubble and not fokn /isfi6ojvlz5f: ; .r a thick piece of glass, say?

When a compact disk (CD) is held at an angle in white)lkt: (ey te4a light, the reflected light is a full spectrum (Fig. 24–56). Explain. (ye4 ttel)ka: What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer togetheoga14v jz gp cg,;:;cmr farther from the center?

Some coated lenses appear greenish yellow when seen by reflected lbcia))i,3k47yy/q n3p o bfq light. What wavelengths do you suppose the coating is designed to transmit compl/o)pfkc3albqyin ,qi347b) yetely?

A drop of oil on a pope(c 8ls/o(qmnd appears bright at its edges, where its thickness is much less than the wavelengths of visible light. What can you say about the index of refractio(oce/p( sl8 qmn of the oil?

What does polarization tell us about 3 gp*n9smz6j0pb i s7othe nature of light?

Explain the advantage of polarizepewr3:m vojb7,vzg9p34g 7oyd sunglasses over normal tinted sunglasses.

How can you tell if a pair of sun 9y4z-;6 trnapo:hupnby ;+cyglasses is polarizing or not?

Two polarized sheets rw),zj*vw8jt/ r4 85 hgbp mzwlv;m eu*otated 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 ofz+m0 xaf)3m 6nag sr,o the sky if the Earth had no atmosphere?

If the Earth’s atmosphere wer*crv wi09 f4z5c-qgeee 50 times denser than it is, would sunlight still be ww4 c eg5zqe0ir cv-*9fhite, or would it be some other color?

  Monochromatic light falling on two slits 0.016 mm apart wayy*ec d- h3+produces the fifth-order fringe at an 8*c+edwy3 ay-h .8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observed a6vwjup1 j3ud6zys 78 jt 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. Succe 5j8qul8pb2mj ssive fringes on a screen 5.00 m away are 6.5 cm apart near the cenumbl58p 28jjq ter of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-N fc ah6e2lx( my0ezc72e laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far 6(ma ccl7yzefh2x0 2e 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 intq th:l*rx .t6xerference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separation ohlq t*t:x r.x6f the two slits?    mm

  If 720-nm and 660-nm light pa q4qwrzxm8m 6(sses through two slits 0.58 mm apart, how far apart are the second-order fring8mx(q6 w4qrmz es for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelength 43; tkx i00e udgi9qgd:60 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a mini dx00ug3qik tg9: eid;mum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through two openi-huurz 6 2)la hb2ej4lngs 5.0 cm apart in a board. At a point 2.0 m beyond the board, at what angle relative to tl -hb2ja2r)u l ez46uhhe “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass is placed in front of the lower slioz6ynb,x 3om8t in Fig. 24–7 so that the two wavesxbno683 ,yzo m 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 jey*yn. l286tx 7j knpthird-order maximum for 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 7k nt jyne.jpx8l62y*the same slits. How far from the central bright spot will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminatedeuslrz+4oyo)bw7j,8 kk t2k + by 544 nm light. Find the distance between adjacent bright fringes on ao tu)wb+7 s4r 2kkkz eoly8,j+ screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air fall1wr b bhhq4((bce 0 wh)0nsik6s 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=1.5 uidyjywuu 0 x.84l1w60) covers one slit of a double-slit apparatus illuminated by 6i.u j0l4yywduu 58 1wx40-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, approximately, does the speed of at:nmbcp 4vu 7n-nm,1red light (700 nm) exceed that of violet light (4001atcnmub 4 :mn7npv-, nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at a od 27yeikwtwe;jc .h9g -.c4v60.00$^{\circ}\,$ 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 l 3pwujhc(u 9kb: in1-jight containing 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 0.0440 mm wide, what is the fxdl;; ))c8oss9lqm) o4trzu m) aot1oull angular width ofqc))1uldm msazo;8t 4oso;) 9txr )lo the central diffraction peak?    $^{\circ}\,$

  Monochromatic light falls on a slit tvts;bc byl + 9x.bh:r-hat 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 :*4;tt rx+eu)ub vxbonm 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.md zl zzgw y;q do.1./ o5u-oobf:w7d illuminated by 450-nm light. What is the width of the central maximum (in cm) in the w o:fouo7lmyo5. ;.dzqzd.b w-g zd1 /diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm faud0 d0rx4ay *.o c;glwlls on a slit. If the angle between the first bright fringes on either side of t .x4wdgo*ydcal0r ;u0he central maximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffractid5yu3a t 8g7omr i75r6/q(,ehklcak von peak on a screen 2.30 m behind a 0.0348-mm-wide slit illuminated by 589-nm likaokqad7lvg cteh5u687 3 5 ,iry /(mrght?    cm

  When blue light of wavelength 440 nm falls on a single svo34: 3r bh3k *f4m7paolr d x9qff5zllit, the first dark bands a3kr7q m3oxf4v45bohl3f*dlr 9f z:p on either side of 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 creattxn/eu qk c)18e-u *ss igj;f4es a central ijse8x;k- g cesuf4nut1q /* )diffraction 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-nmfa98( 8vkaasbhkwg9 s0e mchz 80/x5o light so that the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffrohae 98bkvzhaagm(s 0k wx/88 5 cs90faction maximum for light of wavelength 420 nm?    cm

For a given wavelength q ,m 3e3yi*fbs$\lambda$, 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 maximumt3l -ey.+ztn j;ldpp5 when falling on a grating whosz.ep-tn lpd j;3y5+lte 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 if the third-order occurs at ah:e* -ruxfca sm zr jmed1 a)m730i/f1n 18ee*x uz1hmf 1i- r)m3daamf7s c :/r0j.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 5z2i3pc -rkzkijebz)/18t r6 g89-nm light falling on a diffraction grating is observed at ii1pe2- r /zgkk tczr )6b8zj3a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating ha;npxk(;,x1shx *j 1hm1 qutjws $ 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 normal;o fotkdvj;0 .ly 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 spectral orw v.2dqtn1s 9zmzmvo :/nq 95vder that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light?:/9 9vqmnw2ot s5n1dv vzzq. m Assume normal incidence.   

  Two (and only two) full spectral id6ea:d+ ;d0tcsa-z z zagt/+ orders can be seen on either side of the central maximum when white light is sent through a diffr-acte0 i dt+ :a6sg+d;/zdzz aaction grating. What is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wa jfd-h*29k0ou mgen4 hvelengths from 410 nm to 750 nm falls on a grating with*ge h0f2hm-9u4nk odj $8500\;lines/cm$ 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 known wavelen3 )zy*l q1 mpa*a47eoejpo +owgth $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 specjh*i ekh-i0wxkkxx,9s2 p,(*u (axfetrum 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, what wavelength is moa +fza:xexae c(j+. xs )i4lvsan: *h9st strongly reflected at the center of (.x )e:a*x+s avxzaa9i: lhn 4ejc+sfthe 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 Example 24–8 if the gjw my(c85k(e6 /ctevnlass plates are each 26.5 cm long?mw v6(( j8ey c5tkn/ec    cm

  What is the smallest thickness ukjb*3cm m1 ivaa: t3w+im1p9/m ra/vsu73tkof 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 yel -zparnd7 .am+low ($\lambda\;=\;570\;mm$ 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 (not counting the darb v5wttq 53zk;ttv3. 8cbhuast 6 4l:ok spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a f; 5h8o.sa3q6ct4b v: tvbtkwz3 ttl5u lat 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 optically flaz9wgo-br mi/wta; 9q*t glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28o-gabwr mti 9/;*qw9z dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should the air lazd. bn:,a3v yyyer be between two flat glass surfaces if the glass vy3z :yda b.n,is to appear bright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of materialtm6u fij9u+/(x3ios ( v fe5ue, suspected 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 alcoholw0 2dxc6c73mxr jic v( $(n=1.36)$ 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 lut*7v-05e:bmvua 2 qcyc)0 gslueq3immersed in a liquid, the diameter of t2 7uuysaql:30l*bc5v)u0qe e t c -mvghe eighth dark ring decreases from 2.92 cm to 2.48 cm. What is the refractive index of the liquid?   

  What is the wavelength of the lighbqj wlc )g(/n4b00nsy3b fh 7at entering an interferometer if 644 bright fringes are counsahq/n4 l(fb7 nw)3gbj00y b cted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interfe7eirwrcx4 olc6js l4:m48m, h rometer. When the micrometer is tightened d4mxlo:ij,4hc7 wsec4 8r6r mlown 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 mirr d .:c/cffwi7 -ojir5p6:tq nxgm0 (th yqw,k8or $M_1$ 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. 2w a;16tg nen rcjug+954–59) passes through a small glass container car9j1egtug 5 +cw nn;6ontaining 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 in vacuum. $n_{gas}$

  

  Two polarizers are orientedd j,r yvor)l3 lt:*k0n at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s anglet kxm*b5 *fxr/ for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the lf8dw03 hoi 5pwight is hitting the dih 3i50ww8p fdoamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them iskbl6)s ioh.vxs9( i 9u a maximum. At what angle should one of them be plaxsbk l.i6(9s9 hoviu) ced so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so asd3 +)8givcp i bc9 :8qmxi98 xtgs.oay to reduce the intensity of the incident unpolai3. sb9 )axxdq8ymit8vi8p ccg9go+ :rized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 40 lbmyq047i f.q$^{\circ}\,$ 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 or/.v,ltq r .xr.ncb/eriented 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 b97b9bgtyj g-. w(kwvjky 34jf e for reflections off the surface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewstekjytbbgk7w9f9yj34 vj-(.g wr’s angle from above the surface.
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, eaivb4.7jzzq1rsdrls2p 7pth1jb w/js;::tk 2 ch of whose axis makes apl:jjzt hp7:2qrk2; /b t vds741wjb.is1szr 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength 3yvrz8npybr o p2j4( 9$ 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 from mountain.56tfu zip aagx 62.hnug ap8b:)s-mis or airplanes can interfere with the direct signal froiu ztam6g86papu)x fna-2hsb: g.5i .m 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 se4ey. 1ysg4wv ;bzdx.,lbd0 9e i reeu(parate sources passes through a diffraction grating with ieg4b (xy s0 9u e;rvezbwl,d.dey.41$ 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 passe u9r wr51k0ear bnu9:os 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 of9e9 wuu:o0 rankr5r1b the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from twep.xzvjbd6+6 w5k ks1 o 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 both directions. If the midline is taken as 0vjpkd16 ex s.k+5wz6b $^{\circ}\,$, 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 backush7o1hk 92rx/.es bf from an outside doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, e/o1b9shxuf. sekh7r 2 stimate 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 slit of wib; r,3 +g2b exd 0b(d-svzrlvjdth 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 t. (o-k8e,r a vs ukobe58z.bajhem. When normally incident 460-nm light is reflect ba .rue8o(v,sk58o .zbjae-ked 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 centimeter mus i+a*ca 0es 3*a/d2y2umthfve t a grating have if there is to be no second-order spectrum for any visible waveleniv2u* 3eyst *mhcefa0da2a+ /gth?   $ lines/cm$

Show that the second- and third-order spectra of white light produced by 3ij ri5egfl: 6a diffraction grating always overlap. What wavelengthf3g :6i 5eijlrs overlap exactly?

  When yellow sodium lig6r9klkh1hk7 xzd 9 9ooht, $\lambda\;=\;$ 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 and the pattern is vie2s yhx5gd22a zbsx2c4wed on a screen 2.5 m 2sb y2hc4xzs2ad2g5x from the grating. The incident light beam consists 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 of a clear mai*:kw;.s6kgiduexv, qpi rrt6w5 gi 54v,m p0terial if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce ke,g id k65;ximrtq.vpp i6*uriv 0: 54gw ,wsreflection 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 is incident normally on w04 i5)fud ixea thin sheet of plastic film in u4e fxi)i w5d0air. 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 nwntw*ft 9psgo)du 7),eeded for an anti-reflective 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-zero) thickness for dbz,m+)yp;kdthe air layer between two flat glass surfaces if the glass is to appear dark when 640-nm light is incident normallyy m)b,+; pzddk?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted throu5hxf v9 - az kz to:5ppairj5,2xmq0(wgh a thin film layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 xq- ao5,h z(ip jfpr t95m5a:vk2x0 wzor 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 is thxei4j., 8gnrve Sun when light reflecting off a smooth lake is polarized most strongn48jiv, e rgx.ly?    $^{\circ}\,$

  At what angle should the axes of two Po+ps y+ 8cb6abglaroids be placed so as to reduce the intensity of the incident unpolarized light by an additional +bayc6 gp 8s+bfactor (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 tran3cjnbss6lz 8m7 s /bki:95sx lz7 ptx8smission axes are at right angles. A third polarizer is placsxl s mx 8nbkzzlis :c3 b97j/86t5ps7ed 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 vertilr ,-kzyt :fh(cal, 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 q vpk75qempn zz7 9lf-jw.7z)cm and is pointed at the Moon, which is approximately 380,000 km from the Earth. Assume the laser emits waves of wavelength 630 nm (the red light of a He-Ne laser). Estimate the wid 7q7 vlk95.zpn-f qjwez7zp m)th of the beam when it reaches the Moon.    km

  A series of polarizers ;0 1 wfhx+ikcssw**nh*khk+h are each 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 f(7en y3n3 mvd$(n=1.34)$ 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 waves in phase7hp,f48 hi u ;ehbhp.b with each other. They are located at poi48,bep bhhhh fu.;pi7 nts $S_1$ 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 containin4(zsi;mo;yy c+x vb6wg two wavelengths, 420 nm and 650 nm, enters a silicate flint glass equilateral;ycmvb zyx+;iw6 (o4s 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 lensx rd 7a:wzg+w27:. kfv1hm ysv has one flat surface 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