Does Huygens’ princit; e .bl/nyfeb 1)zkv,ple apply to sound waves? To water waves? Explain.

What is the evidence kciah a:z*s.1 5ad0l*kl fxxf7zilol 0p78 1n that light is energy?

Why is light sometimes described as rays and someti 06:yt,ppa2qy v:wjg ames as waves?

We can hear sounds around corne oy( aa n0afin0cslq 41s-wm82rs, but we cannot see around corners; yet both sound and light are waves. Expl8nf4m0 0cy no-1slaawqis 2a( ain the difference.

If Young’s double-slit experiment were submerged in water, how would thkmdac q55+e8* vj xj:we fringe pa:de5xvj +8 kmj*cw5qattern be changed?

Monochromatic red light is incident on a double slit, and th 8jr zkoz3q+j1y g.*ihe 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 sourcezi y j*g jkq+rho8.1z3.

Two rays of light from tbj); y;zst74q m -rkvjhe same source destructively interfere if their path lengths differ;7ty4 jj)bm-s qv;zkr by how much?

Why was the observation of the double-slit interference pattern more convincwxu3(e k9kflxf+-da 0km/l4w ing evidence for the wave theory of light than the observation of +wkw34lxu0efxf/klad 9 - mk (diffraction?

Compare a double-slit experiment for sound waves to that for ligxmfgtq bv f6tjbbv. )30 -um3*ht waves. Discuss the similarities and differencet )b f33gx.0 mbvbfvj-6qu*tms.

Why doesn’t the light fro, xe)kr9rpam0dpz1 a5m the two headlights of a distant car produce an interference pat5 ad ze1r0 ppxa,9rk)mtern?

Suppose white light falls on the two slits of Fig.-yjzqa8u;i(.gy z)rx,3 celx 24–7, but one slit is covered by a red filter (700 nm) and the other(a -,.cqyzl ; x)egu8yz3i rxj by a blue filter (450 nm). Describe the pattern on the screen.

When white light passes .r1 1lnfxbnzz5+ xo/ zthrough a flat piece of window glass, it is not broken down into colors as it is by a prism. Ezo xbl+xn z .z51fnr1/xplain.

For both converging and diverging lenses, discussw4 u)tjk vrsc3zbhc66y7j:9a how the focal length for red light difa7sr3v y9 wh6j)b6tk4ccj:uzfers from that for violet light.

A ray of light is refracted through three3g sjh4n(o9 at different materials (Fig. 24–55). Rank the materials according to their index of refraction, least tosh4o jn3(g9a t greatest.

Hold one hand close to your eye and focus on a distant light sourcenl: usavex x1+y3l ;( j-fubwwkk6 1d3 through a narrow slit between two fingers. (Adjust your fingerlwx+;3kvsb1lx na3fuw16 ( uy jk-:eds to obtain the best pattern.) Describe the pattern that you see.

What happens to the diffraction pattern of a single slit if the whot 7wm l1b*+xvw xoc azg6j5*7yle apparatus is immersed in (a) water, (b) a vacuum, i7*vc7 6bjo+mxg5 *w1zwy t xlanstead of in air.

For diffraction by a single slit, what is the effect of increasismssnp0(;p/ ;nr6emg ng (a) the slit width,nnpr0s;m 6;ps /m( egs and (b) the wavelength?

What is the difference in the interference patterns formed f /et- eu7e-ap(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 m6-ldqf* ;s0iteh6b p:4a7mccri-pb mu 05cy) many slits, (b) closely spaced s5-;m 7-yb0 mq lrp0me4ct*hci6ba duifcps6:lits?

White light strikes (a) a diffractionv2kt a:( yxw/6 pbp)wb grating, and (b) a prism. A rainbow appears on a wall just below the direction of the horizontal incident beam in each case. What is the color of )aywb2b wv6k(: pxpt/the top of the rainbow in each case? Explain.

For light consisting of wavelengths between 400 nm fm/d75w( c u-yevemlzij3 /hn,h s(g7 and 700 nm, incident normally on a diffractivyhej g-szhc3n7w l /m i(e(dmf/7, 5uon grating, for what orders (if any) would there be overlap in the observed spectrum? Does your answer depend on the slit spacing?

Why are interference fring e*qx7i-hi*j9my(6br7m7b 9* h uxionqav8z wes noticeable only for a thin film like a soap bubble and not for a thick piece of glxzexwmuihmnj9r**9 i b q y7q7b7 ov6(-i8ha *ass, say?

When a compact disk (CD) is held at an angle in white light, th a0 u9b603i38oupun7 qey ofq:5rs bmae reflected light is a full spectrum (Fig. 24–56). Explain. What would you expect to see if monochromatic light was 87r30a o i63ump bq uyofa90ebu:qn5sused?

Why are Newton’s rings (Fig. 24–31) closer together farther from rkg; 5zpukvrc,w99l,s1 . d fethe center?

Some coated lenses appear greenish yellow when seen by reflected lchw5 zmgiaynk 41,,m 7ight. What wavelengths do you suppose the coating ishy ck,751zimm aw4,gn designed to transmit completely?

A drop of oil on a pond appears bright at its edges, where its thick+zyq b6ecl - ajd8v/r o9dfkh i/v53q;ness is much less than the wavelengths of visible light. What can you3efq/ao+y8id / 9dlz v5 b6-vjc; hrqk say about the index of refraction of the oil?

What does polarization tell us about the nature of light?g+uyvo 3r ,var- m h.+hz2r0gm

Explain the advantage of polarized sunglasses over n3yx4 +epgbm1n ormal tinted sunglasses.

How can you tell if a pair of sunglasses is polarizing or noty8d6yh f(fam +s ,w8wd?

Two polarized sheets rotzb( 3pt1)i +xu*w+dsxs mo 2hj53 kmhdated at an angle of 90$^{\circ}\,$ with respect to each other will not let any light through. Three polarized sheets, each rotated at an angle of 45$^{\circ}\,$ with respect to each other, will let some light through. What will happen to unpolarized light if you align four polarized sheets, each rotated at an angle of 30$^{\circ}\,$ with respect to the one in front of it?

What would be the color of the sky if the Earth had no atmnwki5ye rt4b)8-f3 on osphere?

If the Earth’s atmosphere were 50 times denser than it is, would sunlight; rff2d7d kj2u(pce 4f still be white, or would it be some oth2(7;ufcfekp2dr d 4j fer color?

  Monochromatic light falling on twoh8iqsvjkq, 8v h19ct *p-d6 sj slits 0.016 mm apart produces the fifth-order fringe at anvq,qh6- 89 *isp1dt8sjvjckh 8.8$^{\circ}\,$ angle. What is the wavelength of the light used?    $ \times10^{-7 }\;m$

  The third-order fringe of 610 nm light is observplc9u -.aa /09s7l gbnazpat/ ed at an angle of 18$^{\circ}\,$ when the light falls on two narrow slits. How far apart are the slits?    $\mu m$

  Monochromatic light f 8 r( i:k6s0dm1owa*ocz/ t+sut.+zhohvj *z jalls 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. Determine the wavelength and frequency of.c om dr* jus 6/ i0tasozvzw*1t+h(zjho+8k: the light.
$\lambda\;=\;$    $m$
$f$ =    Hz

  A parallel beam of light from a He-Ne laser, with a wavelengthii1e5amm4ub a 3e pc3: 656 nm, falls on two very narrow slits 0.060 mm apart. How far apart are the fri3iepa1eb453 m uam c:inges 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 a-, a (vu;uk8ian yd0frn interference pattern in which the fourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is t;kfy 8,uu0daa( vrin -he separation of the two slits?    mm

  If 720-nm and 660-nm light passes through two slits 0.58 5;i.1rkv gcbzom4, .lq5xex umm apart, how far apart are the second-order fringes fio.x,qu1x cg m55b;4ez .krvlor these two wavelengths on a screen 1.0 m away?    mm

  In a double-slit experiment, cje l s461vwz4it is found that blue light of wavelength 460 nm gives a second-order maximum at a certain location on the screen. What wavelength of visible light would have a minimum at the sam6l4wcvsj 4z1 ee location?    nm

Water waves having parallel crests 2.5 cm apart pass through two openiskgw7r rh2jei: , i53engs 5.0 cm a ke2w rj,i3e:i rshg57part in a 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 gla s2zjdr3/ozt/ube:; p ss is placed in front of the lower slit in Fig. 24–7 3;/z u/tszb2d e:opr jso that the two waves enter the slits 180$^{\circ}\,$ out of phase (Fig. 24–57). Describe in detail the interference pattern on the screen.
24-7
24-57

  In a double-slit experi0hus nu+ 68furwq6 ak5ment, the third-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 br q86af uk5u0 wnh+6ursight spot will the second-order maximum of this light be located?    mm

  Two narrow slits seph*w 4rdg+dos n4e ,w8qarated by 1.0 mm are illuminated by 544 nm light. Find the distance between adjacent bright fringes on a screen 5. dq ewrogn*4s,hd+4w8 0 m from the slits.    mm

  Light of wavelength 480 nm in air falls on two sb3; r(kox d,jz-xx t-ulits $6.00 \times10^{-2 }\;mm$ apart. The slits are immersed in water, as is a viewing screen 40.0 cm away. How far apart are the fringes on the screen?    mm

  A very thin sheet of plastic (n=1.60) covers one slit of a double-slit. ob/z h2fgei9 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 plas gfhb oeiz/2.9tic?    nm

  By what percent, approximately, does the speed of red light (700 h3 hurc-v*nw qcod1c8y )h8 rx0c+ds0nm) exceed that of violet light (4003r1cr-nhdy*cd +0 8x)ohuw0s8 cvqh c nm) in silicate flint glass? (See Fig. 24–14.)    %

  A light beam strikes a piece of glass i: irlerb4 ,-hat 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 cont48jbr.s(c f0hec,k*b kyd )mjaining 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 an na ,yfbx))oboz* jv13nsk7m 3gular width of the central difby on*o,z)nx 1fmv )3a3bksj7fraction peak?    $^{\circ}\,$

  Monochromatic light falls onvyw)) ( :ld 4nepeq1zmu;lfcsxq: -a8 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 f/2z4te *pt.l44xwsbf j i twv4alls 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 lil+jwjqu. zjflr8 ; 7i7ght. What is the width of the central maximum (in cm) in the diffraction pattern on a screen 5.0 m away?zliuj87; j+flrq7 wj.    cm

  Monochromatic light of wavelength 653 nm falls *64x - nvvzbk jpg( 19w2pwznbon a slit. If the angle between the first 6w* zjv( 9nb1pp2nk 4vzgwb- xbright 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 j8*le wxsa(ct 84n1cy m behind a 0.0348-mm-wide slit illuminated by 589-n y 88wln(1s ej*xatcc4m light?    cm

  When blue light of wavelength 440 nm fallh4qk0aly wlf pc8ziyo/ 1fr, n 7u-e 6l.r4c1bs on a single slit, the first dark bands olpyfn4ho6,qf.cl1l/y b- 8r0w1c iuek7azr 4n either side of center are separated by 55.0$^{\circ}\,$. Determine the width of the slit.    $ \times10^{-7 }\;m$

  When violet light of wavelength 415 nm falls on ab w b)jbie6j59 single slit, it creates a central diffraction peak that is 9.20 cm widje5bbj96i w) be on a screen that is 2.55 m away. How wide is the slit?    mm

  If a slit diffracts 650-nm light so that the diffraction maxim(ef vaaof5 m33um is 4.0 cm wide on a screen 1.50 m awaa e(ov5f33famy, what will be the width of the diffraction maximum for light of wavelength 420 nm?    cm

For a given wavelengt cfg.-/cjwjs 17ud y1ah $\lambda$, 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 ma)j6j 5 g d)xpuj:lkuv9ximum when falling on a grating whose slituv)5 k9:ujjl d)6pgxjs 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 w h4np7+px*efptshu(w 7/t)r does a grating have if the third-order occurs at ax4urtw wes7p+(h*ppn h )f7t/n 18.0$^{\circ}\,$ angle for 630-nm light?    $ \times10^{3 }\,lines/cm$

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

  The first-order line of 589-nm light falle7hz1a6vn *u3b 2eyc,9g/k tt r/qfwming on a diffraction grating is observed at a 1y19 2u6ht*,ezv w/3gr m /bec qtfak7n5.5$^{\circ}\,$ angle. How far apart are the slits?    $\mu m$
At what angle will the third order be observed?

  A diffraction grating e /g3l gu,9m 5jk4v yp5oe2/bowtv;blhas $ 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 od2p7tl5di s2c n a $9700-line/cm$ grating is revealed to contain three lines in the first-order spectrum at angles of 31.2$^{\circ}\,$, 36.4$^{\circ}\,$, and 47.5$^{\circ}\,$. What wavelengths are these?
$\lambda_{31.2}$    nm
$\lambda_{36.4}$    nm
$\lambda_{47.5}$    nm

  What is the highest spectral order that can be seen if a grating with 6000l 5yolz9kq8 3l lines per cm is il 89lkoz53l qlyluminated with 633-nm laser light? Assume normal incidence.   

  Two (and only two) full spectral orders can be seen on either side of the centm q7e bqk-6ue)ral maximum when white light is sent through a diffraction grating. What is the eu67 qe)mqk -bmaximum number of lines per cm for the grating?    $ \times10^{ 3}\;lines/cm$

  White light containing wavelengths from 410 nm to 750 :vh/*l7 spcaz nm falls on a grating with s /7alh:p*zv c$8500\;lines/cm$ 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 wavelenge)87 vsufnc.s4r ska7 th $\lambda\;=\;6.328\times10^{-7 }\;m$ 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 spec dt;akhai)c *-trum lines are measured by a $9500-line/cm$ spectroscope at angles, on each side of center, of +26$^{\circ}\,$ 38$^\prime$,+41$^{\circ}\,$ 08$^\prime$ and -26$^{\circ}\,$48$^\prime$,-41$^{\circ}\,$ 19$^\prime$. What are the wavelengths?
$\lambda_{26.72^{\circ}}\;=\;$    nm
$\lambda_{41.23^{\circ}}\;=\;$    nm

  If a soap bubble is 120 nm thick, wha /ebu den9f-81wpfe5- ll6yz zt wavelength is most strongly reflected at the center of the outer surface when illuminated normally by white light? Assume tha8le -f/ ud9zeb15z6- fwepnl yt $n\;=\;1.34$. $\lambda$ =    nm ,which is an    -  

  How far apart are the dark fringes in ddp+86qkc4w93djfq 6 kj.i al Example 24–8 if the glass plates are each 26.5 cm long? i.d6a4ckdld6 j qpkj9fw+ 38q    cm

  What is the smallest thickness khvl(z q3 7o 6id,k*frof 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 s-tr h/2 zo+a1i6elnayellow ($\lambda\;=\;570\;mm$ is strongest) when white light reflects from it. What minimum thickness of coating $(n=1.25)$ do you think is used on such a glass $(n=1.52)$ lens, and why? $t_{min}$    nm

  A total of 31 bright and 31 dark Newton’s rings (not counting jggwhnfq 2a4 a1 pl/tecr1r5es.2 i;+the dark spot at the center) are observed when 550-nm light falls normally on 2lj he w/g;n 2paci+ .1tserq15 rgaf4a 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 zdtt5nj+y2t ra -w(3eoptically 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). How w-nry t+d (tt5a 3e2zjthick is the foil?    $\mu m$

  How thick (minimum) should the air layer be between two flsj .,48jsowo z8te -qqat glass surfaces if the glass is to appear qjw,e 8 o4szjoq 8-.tsbright when 450-nm light is incident normally?    nm
What if the glass is to appear dark?    nm

  vA piece of material, suspected of being a stolen diamond v(8uyxkpa4y ; $(n=2.42)$ 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 alcohovy-;n qausgo01kfe 4)l $(n=1.36)$ 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 ims y f 34* -gmde*b3izr0p *ffmb,3ghyn a liquid, the diameter of the eighth dark ring decreases from grh4-fiy,yg0m*f m*p*bm ebz3dsf 332.92 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 brightv z2n81jlu+q b7 00klemd u ngpbv8p-8 fringes are knpnv8 88g bb+7uqu llez0vpj m0-21dcounted when the movable mirror moves 0.225 mm?    nm

  A micrometer is connected to the movable mirror of an interfnvxjknzmfb+oo( ir30 .l.33a erometer. When the micrometer is tightened down on a thin metal foil, the net number of bright fringes that move, compared to the empty micrometer, is 272. What is the thickness of the foil? The wavelength of light used is 589 nm. . j i03(mvkon3bo3f lran .+xz   $\mu m$

  How far must the mirroxa*cd2-zp)n laf: u y)r $M_1$ 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 interferometebi5, c74rw mhueqi b1rz)d;2mr (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 t4qu52di1,hi7z;) bmrwc e mbrhe interferometer is in vacuum. $n_{gas}$

  

  Two polarizers are orien+1t 2e ;;ibhkck/hukgted 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 ang,zki6a u:qe dq *q,midh,0j; air–glass $(n=1.52)$ surface? $\theta_{p}$    $^{\circ}\,$

  What is Brewster’s angx7n 0kd; h1qjyle for a diamond submerged in water if the light is hittinq7 ;yh1x 0njdkg the diamond $(n=2.42)$ while traveling in the water? $\theta_{p}$    $^{\circ}\,$

  Two Polaroids are alignrp l:nl08f 4tled so that the light passing through them is a maximum. At what angle should one of them be placed so that the intensity is subsequently f l8p0tlrl :4nreduced by half?    $^{\circ}\,$

  At what angle should the axes of twykr ju exn782kphtc4,i b;,s4x/k9 jao Polaroids be placed so as to reduce the intensity of the incidnr tk 8jyjkk,2 xceh;4p / 9xas7u,4bient unpolarized light to
(a) $\frac{1}{3}$ ,    $^{\circ}\,$
(b) $\frac{1}{10}$ ?    $^{\circ}\,$

  Two polarizers are oriented at 47cbfxc-gtgu2jz;6w3 0$^{\circ}\,$ 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 a:yy3 tfmg8w)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 reflections off the surface of water zdn;lo * c+qo;4,*iyn*sg xxwfor light coming from beneath the surface? Compare to the angle for total internal reflection, and to Brewster’s angle from above4+xdyon ; z*l;xso, *nwigqc* 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 Polar( +md-z,kctuh.p:u3wlyb h xi 0h(u p8oid sheets, each of whose axis makeshcu-3zydip(w p umxk:8 lt, h(h .b+0u a 45$^{\circ}\,$ angle with the previous one. What is the intensity of the transmitted beam?    $I_0$

  Light of wavelength atu ghwo wc18eg++ak2/vp6cl;bgw 1hxw 4,7t $ 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 mokcq 2r8j 54rie --kltqslkz((1-fbwluntains or airplanes can interfere willr 54kzjf -kq-rlsc1bi2-(wk qe (8tth the direct 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 sepcqobe3:7j*.bumn2nv m/ g *zrarate sources passes through a diffraction grating with 2. nc :nqzm37v rbjm*/b* uoge$ 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 thr,qv2ag * q2m+srys;l yough two narrow slits 0.60 mm apart. The screen is 1.70 m away. A second source of unknown wavelength prs,a 22l s+*q qrvy;mgyoduces 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 broadc0je ,ja2q7o* bcz f-9wi kvzr*rj8r8 tasts from two identical antennae at the same elevc*i j,a rvb9wkf*je-r828 0tzzo j q7ration but separated by an 8.0-m horizontal distance d, Fig. 24–60. A maximum signal is found along the midline, perpendicular to d at its midpoint and extending horizontally in both directions. If the midline is taken as 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 f8:; omz8jb1o*xtj fzan outside doorway 0.88 m wide, and blows a whistle of frequency 750 Hz. Ignf; t:18jzo* zoj8 xmfboring reflections, estimate at what angle(s) it is not possible to hear the whistle clearly on the playground outside the doorway.    $^{\circ}\,$ either side of the normal.

If parallel light falls on c z(2qil,;vv fa 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 se wsvb qax;z*8hic;, w/lhx ilav350r 3ries of parallel lines across them. When normally incident 460-nm lighc3vr wiha,;z35w 8 hli/0 a*xqls;vbxt 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 centimeter must a gratig ;avcc+i zul,0g1 9)hr8kpving have if there is to be no second-order spectrum ;gh9+ruz 8i a p,iclv gv0)kc1for any visible wavelength?   $ lines/cm$

Show that the second- and third-order spectra of white light producezcr+kc/ +8 zn t5*cvntd by a diffraction grating always overlap. Whatzn/tcr8+*+z nkcvct5 wavelengths overlap exactly?

  When yellow sodium ligh -8/1z.mguyj9yjctc9p5dx lrt, $\lambda\;=\;$ 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 viewed0.t rndr ggu q:ag4b1yl;5wv * on a sgva5w 1tgr b uyln:4r;g*qd0.creen 2.5 m from the grating. The incident light beam consists of two wavelengths, $\lambda_1\;=\; 4.6\times10^{ -7}\;m$ and $\lambda_2\;=\; 6.5\times10^{ -7}\;m$. Calculate the linear distance between the first-order bright fringes of these two wavelengths on the screen.    m

What is the index of refraction of a clear material if a minimum of 150 nm thicd9*;fm:ovhado,)i r; rxirt)kness of it, when laid on glass, is needed to reduce reflection to nearly voaritr*mdrh) f:x) ;dio,; 9 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 (s( cr 9znzr)xuxdf-rt/,9yr incident normally on a thin sheet of plastic film in air. The reflected light is a minimum onf(rnr-,zr)zyux(9 rx/d stc9ly 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 t;k)p6eza bod2d lopn. jo.*;+i a7d u wqi7i:ehickness needed 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 (no)em:bw kx:jkrd 2ee +;yr/zt,n-zero) thickness for the air layer between two flat glass surfaces if the glass is to appear dark when 640-nm light itw :,xe) k/+:;y jr2erkze bdms incident normally?    nm
What if the glass is to appear bright?    nm

Suppose you viewed the light tran7.thljt/4c, a k.gcy jsmitted through a thin film layered on a flat piece of glass. h.t. g/jyjckct7, 4 laDraw 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 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 refl 3s37 lhuh5wizecting off a smooth lake is polah w33zi7s5hul rized most strongly?    $^{\circ}\,$

  At what angle should the axes of two Polaroids be placed so as to reduct73yib1*dnff v. bmv (j;xbs/gls3x +e the intens+1ydmlis b(v gnx.j sv;f/bb tf7x3*3ity of the incident unpolarized light 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 polarizer sheets whose 9m ffe82stu-/ e; j3ova,l qcctransmission axes are at right angles. A third polarizer is placed between the first two so that ilu9mcj ,f8ocq23 seet; af/v-ts 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 i h/n9 w:whzfnu/m8wzsy(8tc9 n 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 a slit of width 1.0 cm and is pointed at the Moon, w+d/hz3;z bsf ehich is approximately 380,000 km from the Earth. Assume the laser +ebdf;zh 3/sz 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 ea ;5i;g xvjqscos (f6-ach 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 g: a( xzxrg.h5b7rek:$(n=1.34)$ 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-MHzkmg6ez6 w9)f7 3fh djdf 7apsmbq*8l+ radio waves in phase with each other. They are located at p7bpf+h63ldj 8d9 mgwf 6km7f*aeqzs )oints $S_1$ 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 wae/b a *x+hehr3o8xma2 velengths, 420 nm and 650 nm, enters a silicate flint glass equilateral prism (Fig. 24broxe h32ax 8* e+h/ma–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 flah*m( gc fr(j)bt 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