Does Huygens’ principle apply ts l(guy y.t;-2 .-b,j sgawakfo sound waves? To water waves? Explain.

What is the evidence that light 0wfs j 42w:wrxis energy?

Why is light sometimes described as rays and sometimes as waves e +unyw *9 ;sd5i0lqhrtu*i(a?

We can hear sounds around corners, but we cannot see around corners; yet fu/9 sm1hst d(..9 joeuttf+z both sound and light are waves. Explain the differe(jt9.t moh9ed1/su.+f fz stunce.

If Young’s double-slit experiment were submerged in water, how would0k d1/gzbh /5otce2dlz, b)rx the fringe patt,/ez tro2g1 / klhx5 0dczb)dbern be changed?

Monochromatic red light is incident on a double slit, and the interfqquikc, mw3:d0 *u 5saerence pattern is viewed on a screen some distance away. Explain how the fringe patt 50uiaq: sduwc3km *q,ern would change if the red light source is replaced by a blue light source.

Two rays of light from the same source destrun7s57 ;cfhk gyptaa5(fw 6e 6juj)a2p;ph d1i ctively interfere if their path lengths diffefg d16 a5ja;(;uhfn7i5c2 psp )jpaykt ehw67r by how much?

Why was the observation of the double-slit interference pattern more conv c8n lstf jt3.azl)62bincing evidence for the wave theory of light than the obsllnj3 f)t.2ac 8btz6 servation of diffraction?

Compare a double-slit experiment for sound waves to that for light waves. Dixu,+n7ohm en5t3s z-hscuss the similarities a e,+soxuh 7n53z-tnhmnd differences.

Why doesn’t the light from t ja 4gi (gayueffnpg; ,;ot+i-evj178he two headlights of a distant car produce an interference patterna;( e;ej 4jivioayg gnup8tf 1 f-+g,7?

Suppose white light falls on the two sbv0;l c.zce r6lits of Fig. 24–7, but one slit is covered by a red filter (700 nm) and the other by a blue filter b6. evclz0 cr;(450 nm). Describe the pattern on the screen.

When white light passes through a flat piece 1cj ic.hyntrqnkj, 3n u.d762 of window glass, it is not broken down into colors as it . q, kjchnntjr3n.ui7dc 612y is by a prism. Explain.

For both converging and diverging lenses, discuss how the focal length n6sfv 6zz8al*mryxu4y+l+m)b 1 m;msfor red lirm6 zzm1*4m6+xal s;+y) buv f nys8mlght differs from that for violet light.

A ray of light is refracted through three different ycv,5n h/6n+ v h*vqrhmaterials (Fig. 24–55). Rank the materials according to their index of re vqy/nr,5 hv+vh 6n*hcfraction, least to greatest.

Hold one hand close to your eye and focus opeyk( zxz*+ed0* k8 fin a distant light source through a narrow slit between two fingersx8k kze e(i df*pzy+*0. (Adjust your fingers to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of aycb as9j3b (ap..q764ceuec v single slit if the whole apparatus is immv 7ys4eub.q3( c9b. a6aeccpjersed in (a) water, (b) a vacuum, instead of in air.

For diffraction by a single slit, gb w g*k9s 5st0)xjz*-uleef4what is the effect of increasing (a) the slit width, and ue-te94 b50 gf )zssk*xwj* gl(b) the wavelength?

What is the difference in the interg. (lx 8cvuo9fference patterns formed (a) by two slits $^{-4}\;cm^2$ apart, (b) by a diffraction grating containing $10^4lines/cm$?

For a diffraction grating, what is the advantage of (a) many slitnhv2 2,k vw u42vimq-gs, (b) closely spaced sk qvmhw,2gvvn-u2 i42lits?

White light strikes (a) a diffraction grating, and (b) m n+.2t ng*/y0howvqga prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. Whatn+v0/qt w*n gh.omg2 y is the color of the top of the rainbow in each case? Explain.

For light consisting of wav +-gmdb ymi76bo(b;xg4af vwyu42yq4elengths between 400 nm and 700 nm, incident normally on a diffraction grating, for what orders (if any) would there be 7 y6v 2+ox mb-4fgi dy;(4uwyabmg4b qoverlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fringes noticeable only for a thin film)zk*89+vbt ypekbo9 a like a soap bubble and not for a thick piek9 *9bbtazy+)kp8ov ece of glass, say?

When a compact disk (CD) aw3; ex10h7t1)t mczh hloy x-is held at an angle in white light, the reflected light is a full spectrum (Fw;x)0 hh1cx 1y zt lte3omh-a7ig. 24–56). Explain. What would you expect to see if monochromatic light was used?

Why are Newton’s rings (Fig. 24–31) closer togeth0sc qy-c )r k)ar2so3cer farther from the center?

Some coated lenses appear greenishe tund: vj;8*ffvd)j*g 66zy(bsox7b yellow when seen by reflected light. What wavelengths do you suppose the coating is designed to transmit compleb8 g:z7o* 6t;vjusxd (f* fn6)y ejvbdtely?

A drop of oil on a pond appears bhf69 s 4;vhrmiright at its edges, where its thickness is much less than the wavelengthshmr6v h9s4; fi of visible light. What can you say about the index of refraction of the oil?

What does polarization tell uc8dlf, ol2w z7y5:x u,axwfn +s about the nature of light?

Explain the advantage of polarized sunglasses overjn2n vr*-2kjz)xv4 ev normal tinted sunglasses.

How can you tell if a pair of sunglasses is p v nbpe/y (4noga6+p/j2 woj+i hcb93folarizing or not?

Two polarized sheets rotated at an angl (8 rou5 k,alkcl2v89ird7vsbe 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 of the sky if the Eart(bqf6y1.6tmh q bvwv2h had no atmosphere?

If the Earth’s atmosphere were 50 times denser than it wlcy7nu4)jemg q l9 7+is, would sunlight still be white, or would it be some olwync4+) u lj 77gemq9ther color?

  Monochromatic light falling on two slits 0.016 mm apr k-/e:pgqh o*art produces the fifth-order fringe at an 8.*g/- eqopkh:r 8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 1p. cy37evhej2tb9j l0 fl s5fnm 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 fal sx9jxmo vqp:i;ervr ; ,ll0.2ls on two very narrow slits 0.048 mm apart. Successive fringes on a screen 5.00 m away are 6.5 cm apart near the center of the pattern. p;l xrros92 q.:i;0, evvjlxm Determine the wavelength and frequency of the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser,xlwrjh:gotr7 o*rbd: 56ju;p lif90: with a wavelength 656 nm, falls on two very narrow slits 0.060 mm apart. How far ap7f9tpx;olhjr u jrlg0: :*i:ob5d 6rw art 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 an56k:+,ntok +)u+ kxnbicti ln interference 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 of thkk cb o+ )l,:+k65nnxt+iiu tne two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 mm apart, hoy .k60gxd m1xaqk1y.c w far apart are ta qgdk6mk0.cy1y1 xx. he second-order fringes for these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit exp ac,w87rb)gat 0etaq.cj2j v5eriment, it is found that blue light of wavelength 460 nm gives a second-order maximum at .bj cetc)v8,gr w 5a7qat0a2 ja certain location on the screen. What wavelength of visible light would have a minimum at the same location?    nm

Water waves having parallel crests 2.5 cm apart pass through -7 ,slif g5;ds0vbjpli c,05 jd3tq rmtwo openings 5.0 cm apart in a board. At a pm,gij cd0l;5b-q3,vp0 sjtr7 fsi ld 5oint 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 placed in front of the lower 7a htjs7v32y8;d +3 mwy1mci6.sngajovi-v xslit in Fig. 24–7 so that the two waves enter the slits iogm2ty;. anvicvw-s+a h7j3 x 8y3s71jvd6 m180$^{\circ}\,$ 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 thir:bm+ c5okp3xki4 3l /.bfvve rd-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 same slits. How far from the central bright spot will thek+4v. cvbf:rel3i5mxbkop/ 3 second-order maximum of this light be located?    mm

  Two narrow slits separated by 1.0 mm are illuminated by 544 nm light/-d ipow-g/l: cyg p1o. Find the distance between adjacent bright fringes on a -ygg/ op -:i1/cdlowp screen 5.0 m from the slits.    mm

  Light of wavelength 480 nm in air fek+:ljtxzb,j::wgstx+ml3e2 g9 e -w w2h-g falls on two slits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.jgl0)-tffr7hjs /5vxo t mw*560) covers one slit of a double-slit apparatus illuminated by 640 w th*o tmjx fvl-fj/50s7gr)5-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, av b-ri 1wj79udoes the speed of red light (700 nm) exceed that of violet light (400 nm) in silicate iu- r9 aw17jbvflint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass at//zsw (j6 kz-z ,y+f qehqrrt1 a 60.00$^{\circ}\,$ incident angle. The beam contains two wavelengths, 450.0 nm and 700.0 nm, for which the index of refraction of the glass is 1.4820 and 1.4742, respectively. What is the angle between the two refracted beams?    $^{\circ}\,$

  A parallel beam of light containing two wavelengtve:* n n0 9npuqthy()ahs, $\lambda_1\;=\;450\;nm$ 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;i xlrn y8q96b3x.smhc:tg (r the full angular width of the central diffraction peak?98txq6 gnc:rmb h( s.3yx ;lir    $^{\circ}\,$

  Monochromatic light fawt.gxs0*r v (ylls on a slit that is $ 2.60\times10^{ -3}\;mm$ wide. If the angle between the first dark fringes on either side of the central maximum is 35.0$^{\circ}\,$ (dark fringe to dark fringe), what is the wavelength of the light used?    nm

  Light of wavelength 520 nm falls on a slit that iss gg(q,fcz iv scu7l/ 02x3z*/wuhnf) $ 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 b 33for) 2 y,yte,uwlkysghb86 y 450-nm light. What is the width of the centretuyy s ,)ofrbh2g8k6yw3 3l, al maximum (in cm) in the diffraction pattern on a screen 5.0 m away?    cm

  Monochromatic light of wavelength 653 nm falls on a slit. If the angle bf06 vx 9.cl/gk sfj3hfetween the first bright fringes on either side of the central ma l3.6sg/h fxfjv0 9ckfximum is 32$^{\circ}\,$, estimate the slit width.    $\mu m$

  How wide is the central diffraction peak on a screen 2.30 m behind a 0.0348-mm-wcy / j,l le/aez1,wf5qide slit illuminated by 589-nm light?/ee1jal zl/y qwc ,f,5    cm

  When blue light of wavelength 440 nm falls on a single slit, aa),v tv47ykethe first dark bands on either side of ce7ea)4v y vt,kanter 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 bo/j.d;0j f fl/ x/aqqslit, it creates a central diffraction peak that is 9.20 cm wide on a screen that is 2.55 m 0 .ff o/qjad bl;qx//jaway. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the dehi(xt(8nl, 3 hub c7do4(adyiffraction maximum is 4.0 cm wide on a screen 1.50 m away, wh(ou d3y d(7c84,hnebh tila(xat will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengthffthi 9ws(cn k- 64qm.t,/ isl $\lambda$, what is the maximum slit width for which there will be no diffraction minima?

  At what angle will 560-nm light produce a second-order maximum bq um,j k9o)gh 0hoqxhxc4 l2f)o6.4u when falling on a grating whose slits are h2q4mk )og).0u 4,jhocxqbx l9uf 6ho$1.45 \times10^{-3 }\;cm$ 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 occ eu;90:cdqo0qqesf t, 7**r xwclncy,urs at an 18.0u, :e0 0n, tysdceqlo*9qq wc*7cx;fr $^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

  A grating has $8300\;lines/cm$. How many complete spectral orders can be seen (400 nm to 700 nm) when it is illuminated by white light?   

  The first-order line of 589-nm light falling on a diffraction grating2wz2 j ixk0o+l is observedo2+i 2l0kzjwx 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 gratin yt )vk,e(kegyl55vkfdim3*z7 689c gi :lydsg 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 dud dhqn6ad 24*-txgqmvq4s 2 m*my *-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 specz9+wpzt h ij mr. 30sostl2/q6tral order that can be seen if a grating with 6000 lines per cm is illuminated with 633-nm la s lsjzh wp2/+6.ioq03tm9rztser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen o73ai( z n2tzda8zbs,nn either side of the central maximum when white light is sent through a diffraction grating. Whaisnaz7 3b,az8tz(n 2 dt is the maximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelength kdoje*lsgvy e :f-,))s from 410 nm to 750 nm falls on a grating with o:gj*dlf) ye)e-kvs, $8500\;lines/cm$ How wide is the first-order spectrum on a screen 2.30 m away?    m

  A He-Ne gas laser which producesc6li(f;z;uzi1d4ky z x:oh4xe p nt )4 monochromatic 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;iwgvih2s:k 7 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 most strongly re mo(ts 1w6jay0flected at the center of the outer surface when illuminated o t(0s16jyw manormally by white light? Assume that $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the darjyvzq3*3tz/ rk fringes in Example 24–8 if the glass plates are each 26.5 zzy v33/q* trjcm long?    cm

  What is the smallest thickne2u40uigjg*zp l 8f go4ss 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 greenisdn) b1 a dku:qft*5.*no(jhhv(v4yaeh 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 (d j,/ciqrg)pf9( 5l9f e ,ukznnot 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). How much thicker is )fu9,z rgd5epkc(i9 fjlq , /nthe center than the edges?    $\mu m$

  A fine metal foil separates one end of two pieces of optiovy / 2u6ujf;y3gzpl0 cally flat glass, as in Fig. 24–33. When light of wavelength 670 nm is inciden0yu yo fzlv63;2p/ujg t normally, 28 dark lines are observed (with one at each end). How thick is the foil?    $\mu m$

  How thick (minimum) should thx9t.c9 f (:tbeby5x9n rc7hzge air layer be between two flat glass surfaces if the glass is to appear gbxct 75c bn y r9txf99e.:hz(bright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, su)l3 atxya41;uwn i)ejspected 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 alcohol:tsz;9s c;.5y2tr2v un l nuut $(n=1.36)$ 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 ii:o-ic3 ouwa z.rkn6t(8enm7v)j5 t (Fig. 24–31) is immersed in a liquid, the diameter ojeiw)z6oi3 nmci-avn ( 7tut5 : ro8k.f the 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 light entering an interferometer if 644 brigh; r+evt0rt c;et fringes are counrt;tevec; 0+r ted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an g uu 9lmzg6::qinterferometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to glg:zm uuq6:9the 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 mirr52nkmdv4b0: ylc(mh5q 1tij dor $M_1$ 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.s1zzis(7 j6kqdp:/k j 24–59) passes through a small glass container containing a cavity 1.30 cm deep. When a gas is allowed to sq s1p/6zkji(:z 7dks jlowly 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 orien ukjdn;p39wgq*cy06gv oc6f s fam:34ted at 65$^{\circ}\,$ to one another. Unpolarized light falls on them. What fraction of the light intensity is transmitted?   

  What is Brewster’s anglaqt;u0jehzk-4 4kgw , atn2g+e for an air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angle for a diamond submerged in water if t:g-(; 8fnu v8bmdpl: fx kx2iuhe light is hitting the diamogu:(knvf:fx8x b u- mld;2 8ipnd $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are aligned so that the light passing through tvih-n sy3j1c5ru54c dhem is a maximum. At what4vrdyu1 cjsci5 n5h-3 angle should one of them be placed so that the intensity is subsequently reduced by half?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so (0(+n sw1sa+l- di ijmetsqs/.owp*icd jc/(as to reduce the intensity of the incident unpolarized lig jqsd//(-*p iceo.0 +m(asjwni w st1 +lsc(idht to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are ori(nshn*a*; hb aented 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 oriente(3rja2ke;z bfzk 74l(zy7 s rkob ezjxf:5g ),d 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 r f5udnr1i(x:icpa89a eflections off the surface of water for light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’ anfx8ii9u: d1cap5r(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 n8zardr wk 9tl8/qn24whose axis makes a qrz/ rlntad8 8w249 kn45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength (vs1c n3kv.. rsckey+$ 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 r.: xgxbmmu t54eflecting from mountains or airplanes can interfere with the direct signal from the sta5 xg.bm x4umt:tion.
(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 dif )s ky 0l6;2sa6e o2guu2xvdgbfraction grating with 2e0 2)vy2 s6 sla dbouxgk6gu;$ 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 0g0 mavpa)2r8dd1 juknm passes through two narrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wa08r0ukjg1 d2pa m)ad vvelength produces its second-order fringe 1.33 mm closer to the central maximum than the 590-nm light. What is the wavelength of the unknown light? $\lambda_2$    nm

A radio station operating at 102.1 MHz broadcasts from two identical anten e mem/wtu:9 3js02 (svjrl9jhm/g3zt nae 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, perpendicms02 :/ljmeh(j t3jm3t9ev /r9zu wg sular 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 an6f, mfs7nf*nh5f nfz / itvv76 outside doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignoring reflections, estimtffn577mni,f*n 6 s hvzf/v6 fate 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 olj3 0/ns-+ r djhrgh3/:jjc cdn a single 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/lp8ty pxw v*; parallel lines across them. When normally incident 460-nm light is reflected from the wing, plpy *v xt8w/;the wing appears bright when viewed at an angle of 51$^{\circ}\,$. How far apart are the lines?    nm

  How many lines per c-s 0d qk/pwns3hl/:poentimeter must a grating have if there is to be no second-order spe hspln:/s0/k3 pwd oq-ctrum for any visible wavelength?   $ lines/cm$

Show that the second- and third-order.hswh ir/vq * u9 kf q8xq4me2jie-i87 spectra of white light produced by a diffraction grating always overlap. What wavelengths overla .hivwi7eq8 x92qkus jfhqme84*i-r/p exactly?

  When yellow sodium ligqh2xrthk/707s/;b, : uvjz)n cfoyo x ht, $\lambda\;=\;$ 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 pattewaf eh+uud(ij0h6g7)j67r j vrn is viewed on a screen 2.5 m from the grating. The incident light beam consists of two wa(j j0g7v)wfujhr e7 uhi66+advelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ 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 minimum of 150y: /phk9+d myw nm thickness of it, when laid on glass, is needed to reduce reflection to nearly zero whe/y+dk p:9mwhyn light of 600 nm is incident normally upon it? Do you have a choice for an answer?

  Monochromatic light of variable wavelength i xxytgb53d 7y/s incident normally on a thin sheet of plastic film in air. The reflected light is a m tyd5x/b 3gy7xinimum 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 needew u,qu2u/i9u.kpx c:ed 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 twol lcph t85qhu6zhus,+s.8c 6w flat glass surfaces if the glass is to appear dark when 666wz8.cuhpl+qh uhl ssc5t ,840-nm light is incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light transmitted through a thin fiw3p6t w:e ,vxylm layered on a flat piece of glass. Draw a diagram, similar to Fig. 24–30 or 24–36, and describe the conditions required for maxima and minima. Consider all possible values of index of refraction. Discuss the relawt6xyp ,ewv:3tive size of the minima compared to the maxima and to zero.
24-30
24-36

  At what angle above the horizon is the Sun when light reflecting oojs7 z vqv/7m +qy(qkknd.m -8ff a smooth lake is pvqyoz.d 8qms kj/n(7kv q+7m -olarized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to red/vo so519( mhirq5h lguce the intensity of the incident unpolarized l5/ ls1rg9oh5o iqmv(hight by an additional factor (after the first Polaroid cuts it in half) of
(a) 4,    $^{\circ}\,$
(b) 10,    $^{\circ}\,$
(c) 100?    $^{\circ}\,$

  Unpolarized light falls on two polariz0g 3fxhk d;be2 g 2lmgll;)9irer sheets whose transmission axes are at right angles. A thix)03mgeild f2h;;g l9 2gkrb lrd polarizer is 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 pl8f9wper qv z:-vc36rtaced in succession with 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 ag-ip5 )qo y8a(7gnin a slit of width 1.0 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 width of the beam when it reaches the Moon.aqp-a8 g o(n7gi5)iny    km

  A series of polarizers are each placed at iglw3q1,-x),8 bw;q5 emh dsn f*laraa 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 ob1j) oe s::nza.g( mi$(n=1.34)$ 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-MHzd wzlo2umx2z52dkp 02s; wg-o radio waves in phase with each other. They a;md-oo52g22dl0 pzx w2kw szure located at points $S_1$ and $S_2$, separated by a distance $d\;=\;175m$, Fig. 24–61. What are the first three points on the y axis where there will be destructive interference? (Destructive interference in this case means that a radio receiver placed at that point would pick up no signal).    m    m    m

  A parallel beam of light containing two wavelengths, 420 nm and xnta n(pdfez(0b;4u9 0zzd1b650 nm, enters a silicate flint glass equilater9bdzea1p0 (znnx(u ftbz ;d04 al 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 surface p*s b/c jt,5eqtmz0l/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