Does Huygens’ principle apply to sound waves? To water waves? Explain.2k mfhyx.)*e: dwt bf r,u:wz7

What is the evidence that light is en6g:0gclfjo7bd ww.v 5 ergy?

Why is light sometimes dp3*nqrr*oo5 k escribed as rays and sometimes as waves?

We can hear sounds around corners, y odn:q +;rxmzbl0+7mbut we cannot see around corners; yet both sound and xr7z0q:b+ml ;m nd yo+light are waves. Explain the difference.

If Young’s double-slit experkhdiv :aa5ktd-+4ac1iment were submerged in water, how would the fringe pattern b1:iavd5-akk c 4 dat+he changed?

Monochromatic red light is bhfqin6w.f c4 vq0/.b incident on a double slit, and the interference pattern is viewed on a screen some distance away. Explain how the fringe pattern would change if the red light sourcbq nw.f0q4.bfi/6hvce is replaced by a blue light source.

Two rays of light from the same source destructively interfere if their (x(7 s:;g5(l4zbghpj q w3qd, uog;yetgz 2eepath lengths differ g(wgesy4b(5 hu3egz x(g: o2;p lze,;7dtqq jby how much?

Why was the observation82g8;r8vz m,8gi ,r accwtqfpu1q-xn of the double-slit interference pattern more convincing evidence for the wave theory of light than the observation of diffraction?,gc8 88i qq, zp8-cnrm 1 uvt2g;rwfxa

Compare a double-slit experiment for soefl61amv; )ew o,-szmund waves to that for light waves. Discuss the similarities and ds;eoafmemz vlw61 ,-) ifferences.

Why doesn’t the light fkibfi/n mn2u62: uv8k sd+)nqrom the two headlights of a distant car produce an interference patqufb: mv2n/s8in u)6+ d2 nikktern?

Suppose white light falls on the two slits ovayc:29v6x7leeff: ln*yio 9f Fig. 24–7, but one slit is covered by a red filter (702 lfyf769y lo9vcax:*vi ee:n 0 nm) and the other by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes through a flat piece of window glass, it u t+ 8 n 8nakeb.0 2ine6ppqt7zk6mt8(ooazm;is not broken down into colors as it is by( tmpoa0m+en6npkz b7i 8ktqtn6 uoa28 e 8.z; a prism. Explain.

For both converging and dive4tqhg /cw 35ofrging lenses, discuss how the focal length for red light differs from two4hc gq/3f5 that for violet light.

A ray of light is refracted through thre r8wtx0g)vfh rxm 19b6kg/ i.te different materials (Fig. 24–55). Rank the g)rk/.hiw81ftrx g9bxt v m60materials according to their index of refraction, least to greatest.

Hold one hand close to youwlr07 +x ujb/gr eye and focus on a distant light source through a narrow slit between two fingers. (Adjust your fingers to obtain the best patte/0r7gxbu+jw lrn.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the whole9enmj) emz1,zp ;g9j7 c:w6l esb.cl h apparatus is immersed in (a) water, (sezm l)l7pch .z , w9 e;1mbjnec:jg69b) a vacuum, instead of in air.

For diffraction by a single slit, what is the effect of increasing (a) the(gdkn 8ol9yeoas,)* b slit wb des( go89a*ol,k)n yidth, and (b) the wavelength?

What is the difference in the interference patterns formed (a) by two slits -5u b nhjl/i3c). tqal lcs1d-$^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slits, (b) clos-ner gf. gcy:94 y2arbely space29 cfe:gbayy 4 .-rgnrd slits?

White light strikes (a) a diffraction grating, 9gb z ex8gkb,*n,xau 6and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of the top of the rainbow in each case? Exp u,gb, *zabxgk 8e9nx6lain.

For light consisting of wavele sfc24s yl;j up51lg5pngths between 400 nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be overlap in the observed spectrum? Does your ass1c;5g2 p juy5l4lp fnswer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film like a soap bubble v k,*g*f.,pit jw9iizx+med9) j3 ycvand not for a thick piec,g.ki * wp m9 tex *yiifdvj,vcz)39+je of glass, say?

When a compact disk (CD) is hbp*0nqn 0y08uk,f:k p)m-i tudi;i gr eld at an angle in white light, the reflected light is a full spectrum (Fig. 24–56). Explain. ,8kq pn:;ii0fpr0* 0- ni mdbgkty)uuWhat would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) c mg25yzazh.o6yqta1u j*)6 dyloser together farther from the center?

Some coated lenses appear greenish yellow when seen by reflec: bfi7snat08 r+cdlli 9*ey*n)l5rib ted light. What wavelengths do you suppose the coating is designed to tl7n5ayfl9brii0i*8:*nd lbstce r) + ransmit completely?

A drop of oil on a pond appears bright at its edgesynkwjox wd(of4ls4umj d2u72:1k7h v5v c( 0f, where its thickness is much less than the wavelkv7vn(jx0o1so d:uum4jh4 cwlk2ydfw 7f( 25engths of visible light. What can you say about the index of refraction of the oil?

What does polarization tell us about the nature of ppc 5;aezr(7v5s6up g (lqc2slight?

Explain the advantage of polarized supl t)*d l24sk2sxq eq0su5ds8fn. cb:nglasses over normal tinted sunglasses.

How can you tell if a pair of sunglasses is polarizing7 vn2*x(,thxz7vzoa7 d5pncj or not?

Two polarized sheets rotated a+uxq -bfd1wcgw8x f1 ,t 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 colnn -q2(, v7aoddjcl6gor of the sky if the Earth had no atmosphere?

If the Earth’s atmosphere were 50 times den rl9exxb u( nxp2b saev);+9)nser than it is, would sunlight still be white, or would it be some other colobv )9(s xl 2exx;en+)p9nbrua r?

  Monochromatic light falling on tdfb) bjl(aa ./; nkcf0wo slits 0.016 mm apart produces the fifth-order fraj0n(;fb)adc/ kl b.finge at an 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 61- eey ,mrwa: .z5c56 ,3nawcpnuwk pk60 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. Succe)( wih8r nzel*ssive fringes on a screen 5.00 m away are 6.5 cm apart near the cen8 eh nz)(wl*riter of the pattern. Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light fro6bdvgpkg hc1m :me4h.sc+bx92n sq1 5m a He-Ne laser, with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart are the fringes in the center of the pattern on4 mk bxgds+ qb2gs6 .5hcp:1hmnvc19e a screen 3.6 m away?    cm

  Light of wavelength 680 nm falls on two slits and produces an interijx3f b gld9f j77u*c n5.y;guference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 mcu*5 g. 93 u;fjydbf i7g7xnjl away. What is the separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slit5rd.3+fq;o y mfjsol/s 0.58 mm apart, how far apart are tf+5 j;d3fso.mqoy/rl he second-order fringes 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 aschov jp3(,9g 2b2ywh / mgd1460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum g1hvg,acw dm2y9j s23o (hb/pat the same location?    nm

Water waves having parallel crests 2.5 cm apart pass thcexgmv7k,ox x5p,r c +01o-tfrough 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” rcf,-ex7xo 0 k5v t+pomc1 x,gdirection would there be little or no wave action?

Suppose a thin piece of glass is pl/rhidu, tq-j wg ,la5*aced in front of the lower slit in Fig. 24–7 so that the two waves enter the slits 180wdqjiuth5g*/a -r l,, $^{\circ}\,$ 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-o0trz8 vk-i6n c (ugf+umb y z0e1o)yd-rder maximum for light of wavelength 500 nm is located 12 mm from the central bright spot on a screen 1.6 m from(10k6- vuz f)t8iuc-ogdbmyr+zne0y the slits. Light of wavelength 650 nm is then projected through the same slits. How far from the central bright spot will the second-order maximum of this light be located?    mm

  Two narrow slits separated by 1w+f .8*io di1awvr0 ua.0 mm are illuminated by 544 nm light. Find the distance between adjacent briauiaf +dr0v*w8w1o . ight fringes on a screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air falls hxg+f yni59u9 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 ld qi-uk y(ald q)7s).of a double-slit apparatus illuminated by 640-nm light. The center point on the screen, instead of being a maximum, is dark. What is the (minimum) thickness of the piay(7qldu qk d)s-. l)lastic?    nm

  By what percent, appyk fi9a w46r*xroximately, does the speed of red light (700 nm) exceed that of violet lightik*f4ay6 9xwr (400 nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a (x.cyf pa2 j1 87pjhp)odp/zvpiece of 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 coo15ex7izp * kko,vp r(ntaining 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 full angular w6.oxb2) kp-l;degya b idth of the central diffraco k 6.2p-bx)adb;ylge tion peak?    $^{\circ}\,$

  Monochromatic light falls on a slitevk e6q/ 6d42huk.oq t 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 falls on gi3/-s2cx ho)dlvpm3a 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 wiiuh pg4)9 sm(tf*ihk x3nr(2 odth of the central maximum (in cm) in the diffraction pattern *m2ix)f3( r(g 9poihhntsu 4kon a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle betweeomf006zw* duuzxq q* a6 ga97dn the first bright fringes on f76qugaqoz daw 9ux z0 m*d06*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 hi+8wdi;hv/j.30 m behind a 0.0348-mm-wide slit illuminated by 5 wj; d+ihvh8i/89-nm light?    cm

  When blue light of wavelength 440 nm falls on a single slit, the first dark b)gd76 o3y(*2:q qid pnpdmx xkands on either side of center are separated by 55p6mgox(npdx:ik72) qq3 d*dy.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wq5 4:kewdb1r- yfcv-w)4vq f davelength 415 nm falls on a single slit, it creates a central diffraction peak that is 9.20 cm wide on a screen that d-ffy4:qv5k-wdqr 1 ecb w4v)is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffraction maximum is 4.0 cm widen.grrup-9 5r g on a screen 1.50 m away, what will be the-g.urr5p 9r ng width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelength e9 ma);dxrvjyq67h,eh :b 4bk $\lambda$, 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 maximumiak1,fs nt.0: czt0f qh:m*bt when falling on a gr1fk, 0t.znqhm: :0cisb* ftatating 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 ifgnl9 -wh/a (wiz6n n )lqh2)oj the third-order occurs at an 18.n nl))lanhw(-gz 9 / ijh6oqw20$^{\circ}\,$ 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 dda-lr-/z 2 (;v: lnrjwna9pcoiffraction grating is observedp- dvw:9rl nn/r(2-;azj calo 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 grating has rutt p qyd+3-q;i,g m 6m6qu2a$ 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 v4 msoz q0 xr5wx*um8xx;-5pr$9700-line/cm$ 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 oe40b/0mp. zx qs*j da)owki u:rder that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm laser light? Assume normal io k04 0*.)mjqi:e/dupbxsazw ncidence.   

  Two (and only two) full spectral orders can be seen on either side1kqssgh)q(:(vd f hwq *n sbd9((we:e of the central maximud1veh dkf( (*q) (qeqssw(bh w ns9g::m when 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 containi ltef+uj 5m01vng wavelengths from 410 nm to 750 nm falls on a grating with5 fut em1lv0j+ $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which produces monochr(eksr( +.vaqacpdr t52 t(qn)vz d.-bomatic light of a known wavelength $\lambda\;=\;6.328\times10^{-7 }\;m$ is used to calibrate a reflection grating in a spectroscope. The first-order diffraction line is found at an angle of 21.5$^{\circ}\,$ to the incident beam. How many lines per meter are there on the grating?    $ \times10^{ 5}\;lines/m$

  Two first-order spectrum lines areb 5u s slgqr7q1kg1 y0rie4c-/ 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,ye-:a 3.5v2xpgncuwq what wavelength is most strongly reflected at the cge-y.a3pn 5xqv2 u:wcenter of the outer surface when illuminated normally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in Example 24–8 if the glass plates arseem+o86-pk6h gdpcw 6q:r fcpij00a qb2 c): e each 2 c crwk6 +qp-i6hpjmes 8c)qo2pg60ba:fd0:e 6.5 cm long?    cm

  What is the smallest thickn7/2n,r i3fnq b90,qog buhwo aess 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 yellow (+tukznp,9qx 2; oqbj/$\lambda\;=\;570\;mm$ 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 ri4 orovz ug 5bh3y-vpq0 vg(nju)i)v/ (ngs (not counting the dark spot at the center) are observed when 550-nm light falls normally on a planoconvex lens resting on a flat glass surface (Fig. 24–31)o rhib z50((vuuy)3v4nj qg gp-vvo)/. How much thicker is the center than the edges?    $\mu m$

  A fine metal foil se5mf5nk f-rf ol f:8q 42dw:mrcd zx8p8parates one end of two pieces of optically flat glass, as in Fig. 24–33. When light of wavelength 670 nm is incident normally, 28 dark lines are observed (with one at each end). Ho2 p5:mdnfw8rr :cxfo 5zd 8mlfqk4-8fw thick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flat g;-bu-z8kd mx ysmpd8.lass surfaces if the glass is to appear bright when 450-nm light is incident normally?zk8;.m b8-- myusdpxd    nm
What if the glass is to appear dark?    nm

  vA piece of material, su;o uw5r),ngud r.ewj1 spected 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 alcoholldn v1:q0j. hzv8qd d, $(n=1.36)$ 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 liquid, the diamra:2fw)y:u4r 9icax*2 3 cwuat bi-ye eter of the eighth dar2) u- i4 cw w3f9b u2arae:i:xtrycy*ak 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 interferometer *t xv2 mr)yt0c;6e p *wfhjix*h7ici; if 644 bright fringes are counted when the* ;cpi*;hxm6 7rivefchj*2 )i 0twtyx movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interferomete)uhj20 3ut ebir. When the micrometer is tightened down on a thin met3 0bj)th2ueui al 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 mirr9;zco yx xbk2d9x;1coor $M_1$ 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. 24–59) passes thzv/e-sffxiab2en z7o+yu3b o4 x e2e8ed04 d /rough 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 friey 8 un4 difaox-7f42/e/0debsev+3x2b zz oenges 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 oriwn7kp*x,s* tv/ o j)nzented at 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–gl x( ho+-s 2nbf3dnvw+aass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if the light ie u8 .,5 rrnt;lkx)xjos hitting the diamokxr,j u nt.o8lx;)e5rnd $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through them is/ ct0jqyh pq6* a maximum. At what angle should one of them be placed so that the intensity is subsequentlyhq ty*6 c/p0qj reduced by half?    $^{\circ}\,$

  At what angle should the axes of two v+smf( c/qadq;o0ia z;j18xvPolaroids be placed so as to reduce the intd;1 08aqzvoa m i+fjx;s/(qvcensity of the incident unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are ori 7nd0/.aeublb ented 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 orie,(cnx c2b0bqop / inxw0ha3-bnli-3 i nted 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 reflectionsdl;;g9 2 k gq6(yhtgmo off the surface of water for light9d(og; gtm;6 gkqhy 2l coming from beneath the surface? 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 Polaroid sheets, each of whose f20; cisk5tqpaxis mk5tci; 0s2pqf akes a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength nl:nvm6,a+v h8 4vuptptcp /s,.u td-$ 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 frox.ly nicxv3m 10b146 :suu6xh yz: wmam mountains or airplanes can interfere with the direct signal from the statixm1 yuy:6hiwu0lc sz n6 va31b.4m:xxon.
(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 separ1cx .ux8p-dor ate sources passes through a diffraction grating with ocd8x.px-r1u $ 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 th a fasgxx 1zfvhv928 hd ds0:m/x0;bb8rough 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 the9bhm8vxh dxv :;/azfab02x0 1fs s g8d central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcacdxz/u hqsnsn s1rkh/33 e:37sts 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 horizos/ rsz 3:1q3c37nhhnkex/d u sntally 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 fcvbb ;uyk+e. +v;gr(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 hearke y+.ucg+r; (b bvf;v the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on a singlek/9g:ap uugm 4 slit of width D at a 30$^{\circ}\,$ angle to the normal, describe the diffraction pattern.

  The wings of a certain beetle have a series of parallel lines ac avz*ngr0ua(rbe+r7tim j5358 uz( across them. When normally incident 460-nm light is reflected from the wing, tzt8( * e3+vruu5bnam0arzj5 c(g7 airhe wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per centi*q 0n6 mup-gvlmqd1x 0meter must a grating have if there is to be no second-order spectrl nq mxp010du6 *vm-qgum for any visible wavelength?   $ lines/cm$

Show that the second- and tzmqg5f)c4 c -go2q3ve hird-order spectra of white light produced by a diffraction grating al qc4f ogc )-m53zg2evqways overlap. What wavelengths overlap exactly?

  When yellow sodium light,ctu*9zn4so x 1xg)wsbx g5:3g $\lambda\;=\;$ 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 andophu/.ees)c9+0zdea7eu pvry wq4) ; the pattern is viewed on a screen 2.5 m from the grating. The incident light beam cs a/e 9cvppu ywr;.) ee7d4oe)z+0hq uonsists 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 cle/ks4rod8*f n8xo gs; har material if a minimum of 150 nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero when light of 600 nm is incxr*o4s ;8hs no/d8kgfident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable h c+/ y)id/ks s/e: fuyj38xnewavelength is incident normally on a thin sheet of plastic film in air. The reflected light is a minimy+sf ee/y c8s:3/niu djx/ hk)um 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 neejzoo8(1olgh: r 2s:oided 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 the air layer between two 4n / tfz/ uoqlg0dh o*7a/ky(z.n-e)jts7wsr flat glass surfaces if the glass is to appear darkzotnrwdoa /yhgn )s0tel-*( 7f/74zku qj./s when 640-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the lizpliz /f kuf(1 si4d rz-j0i+:ght 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 /i lr-si id1 :0zjkzzfup4+( fand 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 the Sun when light reflz b -f 7c fw5ku59r6ci(ps on-n;oe0vxp m-c0eecting off a smooth lake is poc9i0 fu w -rcenp pbk-f-o7(6vxzc s;n5e50molarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be plaumfde(i.+e il2hf p4 c ui+21lced so as to reduce the intensity of the incident unpolarized lighd2( . 1ce+u im2pli+if fle4uht by an additional factor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light fallsdwclo )li ); )jwspt( iag4s./ on two polarizer sheets whose transmission axes are at right angles. A third polarizer isd; gp .)tw))4ac(jssioiwl l/ placed between the first two so that its axis makes a 62$^{\circ}\,$ angle with the axis of the first polarizer.
(a) What fraction of the incident light intensity is transmitted?    $I_0$
(b) What if the third polarizer is in front of the other two?

Four polarizers are placed in succession with their axes 03k6 g oekn,edsa*)i yvertical, 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 poia8fjq hb3s(14fhd . xdnted at the Moon, which is approximah1d8 s fh3bfa4j.dx (qtely 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 the beam when it reaches the Moon.    km

  A series of polarizers are each ppdn: bbr81y1bzxonmm9h 6/l1 t,;u xme5niw:laced 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 .p.y7bsm ngdav:q r (60ashv 9$(n=1.34)$ 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-MHzgu-+9wiji)*q8 j2w *gampmemq6maatks f4 .* radio waves in phase with each other. They are mj9i*qs46egwmja* 2gaqu)i +tfm mpw* 8 .a-klocated 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 650 nm, enters ahpeyiy.+t f/ht( z/0) lysn8j silicate flint glass equilateral prism (Fig. 24–58). nesy)tfiy8z+yht/ (/j0l h.p
(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 ysi eeih0n3 n uu2d,o:+l3)v dlens 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