Does Huygens’ principle apply to sound waves? To 23xm0fv13mhulgwy0j 3.ni7 jf; oiqcwater waves? Explain.

What is the evidence tha dev+ o:m15bn9dqtc*z t light is energy?

Why is light sometimes descrig )ggnd wp 8-dp-;wey0bed as rays and sometimes as waves?

We can hear sounds around corners, but we cannot see;r/vzdixzh tq23ua76rkg ;+g around corners; yet both sound and light are waves. Explain ak 3+r6i/utg r 7hg zvzqdx;;2the difference.

If Young’s double-slit expes6w)7aglpag3;m-z2lfakv2 h3i :a f hriment were submerged in water, how would the fringe pattern be changed?ih lgza-7a2fkmv:a );lgw2ahp63f s3

Monochromatic red light is incident on a double slit, and -3nicmq:)gh u the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light source is replaced by a blue light source. mgcn- u3)hiq:

Two rays of light from the sl0i2din 5l3p zame source destructively interfere if their path lengths differ by0l5np di 2z3li how much?

Why was the observation of the double-slit interference p*zy-kgnstm4yu;wx /.r5w r(mattern more convincing evidence for the wave theory of light than the observati-y (w 4nztgrwxk5sm .;yr u/m*on of diffraction?

Compare a double-slit experiment for sound waves to that for light waves. Disccpg u26 hwfe85uss 6 p8gufe5cwh2the similarities and differences.

Why doesn’t the light from the two headlights of a distant car produce an cz 7i/s)fvmm tqpb25a1t9 7hwinterference pattern?zv/2t5tim )s h 797fm 1wbqacp

Suppose white light falls on the two slits of Fig. 24–7, buqid:gbo o lk0zjkr;nd +s)* .2t one slit is covered by a red filter (700 nm) and the other by a blue filt+ :ik0qr*zdld o2so.k ng b);jer (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it is not broken d/.khyb nnmb6-o7 + q1jqdmr1sown ik/q1n1b 6 hb7+-md.soqjrnm ynto colors as it is by a prism. Explain.

For both converging and diverging lenses, discuss how thx0zgip5wtny -f8(3 55 s owdmfe focal length for red light differs fw5 (f3npiy mdwt z5o x8f0gs5-rom that for violet light.

A ray of light is refracted through w+np9 +fypuk1three different materials (Fig. 24–55). Rank the materials according to their index of refraction, py9+ k 1wfp+nuleast to greatest.

Hold one hand close to your eye and focus on a distant light source through a nfs q 3.)z(u-c8efpo pnarrow slit between two fingers. (Adjust your fingers to obtain the best pau-83fzn(q) e o pp.sfcttern.) Describe the pattern that you see.

What happens to the di2 .rjnf(tse9a (j+eywffraction pattern of a single slit if the whole apparatus is immersed in (a) water, (b) ayej+a ((s9ntr.f2jwe vacuum, instead of in air.

For diffraction by a single slit, what is the effect of increasingzb e-sr 36rp1/dc qp);suhm5i (a) the slit width, and (b) the w-ip 5b es1qh6p;rsc/rumz) d3avelength?

What is the difference in the 1; s 8y9txt2*y2 y6ovshqnub)gv j+ npinterference 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 qz )xit yleb 2y51da65advantage of (a) many slits, (b) closely spaced sla6tyx1ly) zqb5 d ei25its?

White light strikes (a) a diffraction grating, and (b) a prism. A rainbow f*s9cr7y4xue9eh3k yappears on a wall just below the direction of the horizontal incide3 r9ehksex9ufyc y *47nt 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 an9i x *lo9dw-ng kv0 y6x26nhiyd 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer d9n6 dnyxoy9h0ii*l wkg- 2v6xepend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap bubble)gjba) h,i;eyr: nao+ and not for a thick piece of g,+a;bi:e ))r joghanylass, say?

When a compact disk (CD) is held at an angle in white lightq9h+4fn-*io*j jl)-.iehn )woky yqg, the reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light wo y*)+ qq-.*- nfink)hjwye49h oijlgas used?

Why are Newton’s rings (Fjnn:7v ;1mmmewlx s+ :ig. 24–31) closer together farther from the center?

Some coated lenses appear greenis59 we9wqu9* t6kyxszlh yellow when seen by reflected light. What waveu6z9 qyxktl e95ws9w* lengths do you suppose the coating is designed to transmit completely?

A drop of oil on a plzayssr 223a, dxg5 vusc--f0ond appears bright at its edges, where its thickness is much less than the wavelengths of visible light. What can you sgczru,x as0-vs232 f5y asl -day about the index of refraction of the oil?

What does polarizatio)f xw.jke(4flna/4 z kn tell us about the nature of light?

Explain the advantage of polarized sunglasses over norr/aplsewb154hrc (fqb 0v0* cmal tinted sunglasses.

How can you tell if a pair of sunglassesxu )2 l5jvw21yb v.8bj ;+ msmixu0nvc is polarizing or not?

Two polarized sheets rotated at an angle of 9mbti/2,c q 5fy ccg:f*0$^{\circ}\,$ 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 thee or1((d7gre k sky if the Earth had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it is, woeet*i( 7.gz eruld sunlight still be ie7.etrez* g (white, or would it be some other color?

  Monochromatic light falling+)s:fv: u:6v9fh xcm jhe eyl0 on two slits 0.016 mm apart produces the fifth-order fringe at9lvvsh:) j0f+xymh fc6 u e:e: an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm liu8rlp*,gl* 62aglidsght 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 slitsdr;guz40/ p-ciins - s;0pll+p(bl hs 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apazillgp04s-s( u;hncp b l- ;0s+ir /pdrt near the center of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of lig-qp4zflfx a:6;, ixmnht from a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart ar4,aq:ml;ixx -p nff 6ze 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 interference pattev4x z t1oegui;)m:69 f+ fdtbern in which the fourtht9g)ef41 ou: etzvx ;i6md+bf-order fringe is 38 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 8;z zb4*u o;d gi7kag6 ib7c cmshu;7aslits 0.58 mm apart, how far apart are the second-order fringes for these two wavelengths on a screen 1z7b 7a bczug8ig7 coh i;s;dmk;a u64*.0 m away?    mm

  In a double-slit experiment, it is found that blue light of wavelength 460 n3p/*q7 zoyl.l cuoqj2m gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimu l pqqyc/7uo*z2.3l jom at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass t 6cj.)n2j5 9qyd:*ud hwrl jcbhrough two openings 5.0 cm apart in 92j5buy:n j)clh*jdq6dr .w ca board. At a point 2.0 m beyond the board, at what angle relative to the “straight-through” direction would there be little or no wave action?

Suppose a thin piece of glass is pl umqy 65nj 6m/des,hi)aced in front of the lower slit in Fig. 24–7 so that the two waves enter the njdq )mei,/ ym s5h66uslits 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 th xa3:w2w7y p.*byyz /t tjfm7tird-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 the samt* xf:jpyw/az37 tyt2w .m by7e 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 illumin rzc4h1fr0/rnc/4j nn3e z* namnce 5*ated by 544 nm light. Find the distance between adjacent bright fringes on a screen 5.0 m fra3rzr 4/j/nh5nzn mf1 0cc* e4*crn neom the slits.    mm

  Light of wavelength 480 nm in air falls on two s 2h ;/zqhxnzy*;dw. :iefyq)blits $6.00 \times10^{-2 }\;mm$ 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) cra+*bz+ wnvv xbz277q64 oaqoovers one slit of a double-slit apparatus illuminated by 640-nm light. The center point on the screen, instead of n+72ovqzobx 4 q v 7+zabwa*6rbeing a maximum, is dark. What is the (minimum) thickness of the plastic?    nm

  By what percent, approximately,lk5 9y2nir1 :c *fuq:e +lpwwz does the speed of red light (700 nm) exceed that of violet lightql i2feylnwu c+ 9:5zwr1k*:p (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glp.0e(,aq8131 s 2rey /dwyov blwu slgvxav+4 ass 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 c ll una(sj-u 0/*ctxlz5 8:rl beko(p(ontaining 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 fallo s+xls)2abr jf55;6 ircpfz 2s on a slit 0.0440 mm wide, what is the full angular width of the central diff r;2+s 2 acop 6fj55rl)fxbiszraction peak?    $^{\circ}\,$

  Monochromatic light fa;0d0x naafeltv8l : m 4f:.qbulls 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 zz7euu xa:d h2el;a97nm 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 the widtzo1vbqtt.9 c,z s;3n 0rzoaj,h of the central maxiq0zt t 1sjr.c;3abn,9zo o,vzmum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelengt* 0k2:4n; qzzt:p cvxeir lzn3h 653 nm falls on a slit. If the angle between the first bright;np 2r c3i lz0tk4*n:v:xqzze 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 behind a 0.034 wyi0i 0h+)muq8-mm-wide slit illuminated by 589-nm lig iw0 q0)muh+yiht?    cm

  When blue light of wavelength 440 nm falls on a single slit, the fi w,w6e wsq9ito*,1qqvrst dark bands on either side ofqetq,w*1 9 oq,wsi 6wv 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 sinlb0mfy j fbt ;q8tk;*3gle slit, it creates a central diffraction p*;tqt mjbkb30f8y;f leak 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 ;h8c * fjqa;epjz .qr7light so that the diffraction maximum is 4.0 cm wide on a screen 1.50 m away, what will be the width of the diffraction maximum for light of wavelengthcqp.j;r azq7* fhj e8; 420 nm?    cm

For a given waveleng 1a; hzd;4:uz.ecnp jeth $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm lighi 8jg 2wk-v;cnp*nc *ek 41keet produce a second-order maximum when falling on a grating 8 2ccpk1 evk;ej4gk ne*-win* 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 does a grating have if the third-order occu7h ppx1l0pd v77.zoka rs at an 18.0px7017 z odvha7. lpkp$^{\circ}\,$ 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 linzr 9;, )nqk c.whkdo 7/hub:hght falling on a diffraction grating is observe h .dnzho uh/7kbrkw9);qcn,:d at a 15.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction gratinwa5 . d+3tund)i;erds9 (0tai h6ulhq g has $ 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 hclol(n 1y ,3za $9700-line/cm$ 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 that can be seen if a grating with 6000 lin7bxpf22oy p jh .vms84es per cm is illuminated with 633-nm lv28spj 74yh. 2fm pobxaser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on either side o 4iiklidpdp -zgmrz*9 *)tf6 9f the central maximum when i k*lg9d6f*ir zdzp4ti)9m-p white 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 wavelz-8ozo )dni0om +y z:*v2v efq4z* ozbengths from 410 nm to 750 nm falls on a grating withfqomo8z z:*n-)zz v y eo0ozd+biv2* 4 $8500\;lines/cm$ 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 wavelenkmiz i9l//6j:qdy 4q ugth $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 mea t hx:wg5yoe2re4 quab: 08+gvsured 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 strongly reflected ahn5; vud8cde oiw y857ckv23 g(p+pf wt the center of the outer surface+nhpwie5v; 52(uc cv3 o8dfygw kd7p8 when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes ippcq4n cfoynhf k(**s85 f kq) 67ju1on Example 24–8 if the glass plates are each 26.5 cm loncqnkcffnhp )*yk5fp7 8 j*q1(4o6soug?    cm

  What is the smallest thickness of j )/ sguno yojgr)0o ry;0.(vpa 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 greenz*qao6us gg1 -82 9fqln0rbnqish yellow ($\lambda\;=\;570\;mm$ 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 ((lbjgz4s cb 5g3t)8ah0a;zq)9kmu t cnot counting the dark spot at the center) are observed when 550-nm light falls)(3at4 9clhgbt0j mg5q8au; zbk)c zs 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 optically m03yb7qw h-c c )kg0nhrw 02jkflat glass, as in Fig. 24–33. When light ofmg-c0yh k07)3wc qn bjr2k hw0 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 between7j gc0hw1p +gvuc1gb7 t 56svk two flat glass surfaces if the glass is to appear bright when 450-nm light is incid v gc6bw 0571hjgc7uvkg1p+tsent normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected 8zn1wz3d)thpmh;pck r 78cqg t87 ca 4of 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 alcoh uop6:s.uv 6mgi2emw/ol $(n=1.36)$ 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*ir:ee,y mu,hy*c sm) apparatus (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 refractiuh*m e:yeiy), sc,rm* ve index of the liquid?   

  What is the wavelength of the light entering an intem. m1xpd;u /0p:zo3 34 (lrbofdyqmbjrferometer if 644 bright fringes are counted when the xd yqpub; 1mrd mojf: 3p(l.o04mz3b/ movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interfer 1enmgq th4))oometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared )4tm1) qn egohto 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 q y4nkreel:b5bfy 26( s o :6s-helly*$M_1$ 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 ;67gbj4gmgaccv (jcq1; 1v6hi 4oten(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 interfaq;co6 gvb1etjgvjg4 inhc(; 1m7 4 c6erometer is in vacuum. $n_{gas}$

  

  Two polarizers are opoy4w j 0ot7d(riented at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s an8s5/3 y+ztni c8gqk+p7u lsrkgle for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light ii*f)taq35rq ys hitting the diamfqq3ti *5yra )ond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are ali-9y, qo imfi2baa2:bg9y6 ebegned so that the light passing through them is a maximum. At what angle should one of them be placed so thaboy q e9-:m 6yf2g2bea ia,ib9t the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduc;drldg pxd o )qj506i4e the intensity of the incident unpolarized light to 0i;jgdxldqo465 prd)
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oribw 86qc 8k+.wijua x-qented 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.nj7f s43r 6bba0$^{\circ}\,$ 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 utzmq +3iihb. t;(4w jangle be for reflections off the surface of water for light coming from beneath the sur+.;3wi4(t ituz mbh jqface? Compare to the angle for total internal reflection, and to Brewster’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 Polar7wfvimjb24uy:-a3 qb z5w; lqoid sheets, each of whose axiu-fqa:lqb2mi;y z74w v jw3b5s makes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength mo c-:sw6 rohxs,ov *5$ 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 mountai (n+oc *2cln hoc3-i qdltl.q:ns or airplanes can interfere with the directqlho23on+ccq*l: ( c. tli- dn signal 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 separate sources passes through a diffraction gra32xa+bb4ig 6 7sk+nfrzem( yxting with +2m7x +nb46faixsr( kybe 3gz$ 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 55k4uuv7z ,onv 90 nm passes 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 th v5ko4n,zuv7ue unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts fi /jva7igkka )x +l ;4(qtcju0rom 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, perqx7(;0a+c/ aik tvgju4k) jlipendicular 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 outsv 1. z-bcjcz+8wpjyg ,ide 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 cle ,wzb81j gcp+c.yvz-j arly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a single sli62 k 0vuqq,7mxirc:xa t of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series0 cijkzbd/:7a of parallel lines across them. When normally incident 460-nm i j0c/a:zd kb7light 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 centimete5ruf ve4cd( (kr must a grating have if there is to be no second-order spectrum for any visible wavelength?d45 ke(v ufcr(   $ lines/cm$

Show that the second. a)jxbd tuh(d8jt;e 3- and third-order spectra of white light produced by a diffraction grating always overlap. What wavelengtdej x8t)du.; jbah3 t(hs overlap exactly?

  When yellow sodium light,xiz6b i8z8dofx s2,3 s $\lambda\;=\;$ 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 viewed onck sl4.5 -f)+ wkuzd8evc(kwb2z 6prl a screen 2.5 m from the grating. The incident wvb- w6. e4+kz5zpckfu 2d(l 8rck sl)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 material if a minimum4l s4n i()7yl0fyprqi ylf)+nz* 1rsf of 150 nm thickness fpir l )n4l+1y(4rls )qfzni syy0f7 *of it, when laid on glass, 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 variable wavelength is inci- r( aal3wakotc s+b,)dent normally on a thin sheet of plastic film )( kaora3+acb-t,w s lin 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 coatingaztjh6mk6v9y7-i fj2 ad0ok6 $(n=1.38)$ 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 thqc:llg ;n) w vtz.t-:re air layer between two flat glass surfaces if the glass is to appear dark when 640-nm light is incidentl t .:n-gr; lvtwcz)q: normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a thin film layer -cxr ;a2d:ehv(to a0med on a flat piece of glass. Draw a diagram, similar to Fig. 2x rd oah-ma2c(;:0evt4–30 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 hor7p 558c.s ffbpwfa uz5izon is the Sun when light reflecting off a smooth lake is polarized most swu55faf8 pp.b7fz 5 cstrongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduceg(xnap3:df55t hob b. the intensity of the incident unpolarized light by an additional factor (after the first Polaroid cuts it in halfx.f ad: npt35(5bh bog) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polarizer sheets whose transmission axes are at+o+eppi +2 f hti4luose 4en-. right angles. A third polarizer is placed between the fh2enuop+ e tole. +4p-+fis i4irst 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 wit:x (mr(fgank 0h their 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 pointed at the Moon,yh;5 2 s9-k-fcqvo(( pq nzydw 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 width of qqvk w;(yn- -zh9dsp2 oc(f5ythe beam when it reaches the Moon.    km

  A series of polarizers:gx gvg33frt,-vy c)s 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 +bxm*r77- e(z2 qjgf ecvh-3g 5s t5bqyxh- rp$(n=1.34)$ 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 phaih/ acr*vx)(fn h *l,, lud0hjse with each other. They are located atvn ,r(axh hdl)0* ,lfj*c /uih 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(-sp aws2klskr1ahp)rn( - m9 nm and 650 nm, enters a silicate flinal 9ap(sw-k(r h)mkr -sn2s 1pt glass equilateral 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 surl4ae5nnm 6fr6*5mo stface 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